diff --git a/src/lib/time/timevalue.hpp b/src/lib/time/timevalue.hpp
index 926d9ea0e..e497979df 100644
--- a/src/lib/time/timevalue.hpp
+++ b/src/lib/time/timevalue.hpp
@@ -565,25 +565,25 @@ namespace time {
         , dur_(length)
         { }
       
-      TimeSpan(TimeValue const& start, Offset const& reference_distance)
-        : Time(start)
-        , dur_(reference_distance)
-        { }
-      
-      TimeSpan(TimeValue const& start, TimeValue const& end)
-        : Time(start)
-        , dur_(Offset(start,end))
-        { }
-      
       TimeSpan(TimeValue const& start, FSecs(duration_in_secs))
         : Time(start)
         , dur_(duration_in_secs)
         { }
       
+      TimeSpan(TimeValue const& start, TimeValue const& end)
+        : Time(start<=end? start:end)
+        , dur_(Offset(start,end))
+        { }
+      
+      TimeSpan(TimeValue const& start, Offset const& reference_distance)
+        : TimeSpan{start, Time{start} + reference_distance}
+        { }
+      
       TimeSpan()
         : TimeSpan(Time::ZERO, Time::ZERO)
         { }
       
+      TimeSpan conform()  const;  ///< @return a copy conformed to time domain limits
       
       Duration&
       duration()
@@ -715,6 +715,13 @@ namespace time {
     return symmetricLimit (res, Duration::MAX);
   }
   
+  inline TimeSpan
+  TimeSpan::conform()  const     ///<  @note: implicitly capped to Duration::MAX
+  {
+    return Offset{*this} + dur_ <= Time::MAX? TimeSpan{*this}
+                                            : TimeSpan{Time::MAX-dur_, Time::MAX};
+  }
+  
   
   inline
   TimeVar::TimeVar (FSecs const& fractionalSeconds)
diff --git a/src/stage/model/zoom-window.hpp b/src/stage/model/zoom-window.hpp
index 776befd69..54603036d 100644
--- a/src/stage/model/zoom-window.hpp
+++ b/src/stage/model/zoom-window.hpp
@@ -224,8 +224,8 @@ namespace model {
       
     public:
       ZoomWindow (uint pxWidth, TimeSpan timeline =TimeSpan{Time::ZERO, DEFAULT_CANVAS})
-        : startAll_{timeline.start()}
-        , afterAll_{ensureNonEmpty(startAll_, timeline.end())}
+        : startAll_{ensureNonEmpty(timeline).start()}
+        , afterAll_{ensureNonEmpty(timeline).end()}
         , startWin_{startAll_}
         , afterWin_{afterAll_}
         , px_per_sec_{establishMetric (pxWidth, startWin_, afterWin_)}
@@ -673,11 +673,13 @@ namespace model {
        * - visibleWindow ⊂ Canvas
        */
       
-      static TimeValue
-      ensureNonEmpty (Time start, TimeValue endPoint)
+      static TimeSpan
+      ensureNonEmpty (TimeSpan const& span)
         {
-          return (start < endPoint)? endPoint
-                                   : start + Time{DEFAULT_CANVAS};
+          return TimeSpan{span.start()
+                         ,util::isnil(span.duration())? Duration{DEFAULT_CANVAS}
+                                                      : span.duration()
+                         }.conform();
         }
       
       /** Assertion helper: resulting pxWidth matches expectations */
@@ -847,8 +849,6 @@ namespace model {
         {
           FSecs dur{afterWin_-startWin_};
           REQUIRE (dur <= MAX_TIMESPAN);
-          REQUIRE (Time::MIN <= startWin_);
-          REQUIRE (afterWin_ <= Time::MAX);
           startAll_ = max (startAll_, Time::MIN);
           afterAll_ = min (afterAll_, Time::MAX);
           if (dur <= _FSecs(afterAll_-startAll_))
@@ -874,6 +874,8 @@ namespace model {
             }
           ENSURE (startAll_ <= startWin_);
           ENSURE (afterWin_ <= afterAll_);
+          ENSURE (Time::MIN <= startWin_);
+          ENSURE (afterWin_ <= Time::MAX);
         }
       
       void
@@ -922,8 +924,8 @@ namespace model {
       void
       mutateCanvas (TimeSpan canvas)
         {
-          startAll_ = canvas.start();
-          afterAll_ = ensureNonEmpty (startAll_, canvas.end());
+          startAll_ = ensureNonEmpty(canvas).start();
+          afterAll_ = ensureNonEmpty(canvas).end();
           ensureInvariants();
         }
       
@@ -934,12 +936,11 @@ namespace model {
       mutateWindow (TimeSpan window)
         {
           uint px{pxWidth()};
-          startWin_ = window.start();
-          afterWin_ = ensureNonEmpty (startWin_, window.end());
+          startWin_ = ensureNonEmpty(window).start();
+          afterWin_ = ensureNonEmpty(window).end();
           conformWindowToMetricLimits (px);
           startAll_ = min (startAll_, startWin_);
           afterAll_ = max (afterAll_, afterWin_);
-          px_per_sec_ = conformMetricToWindow (px);
           ensureInvariants (px);
         }
       
@@ -949,12 +950,11 @@ namespace model {
       mutateRanges (TimeSpan canvas, TimeSpan window)
         {
           uint px{pxWidth()};
-          startAll_ = canvas.start();
-          afterAll_ = ensureNonEmpty (startAll_, canvas.end());
-          startWin_ = window.start();
-          afterWin_ = ensureNonEmpty (startWin_, window.end());
+          startAll_ = ensureNonEmpty(canvas).start();
+          afterAll_ = ensureNonEmpty(canvas).end();
+          startWin_ = ensureNonEmpty(window).start();
+          afterWin_ = ensureNonEmpty(window).end();
           conformWindowToMetricLimits (px);
-          px_per_sec_ = conformMetricToWindow (px);
           ensureInvariants (px);
         }
       
@@ -997,7 +997,6 @@ namespace model {
           adaptedWindow = max (adaptedWindow, MICRO_TICK); // prevent void window
           adaptedWindow = min (adaptedWindow, maxSaneWinExtension (pxWidth));
           establishWindowDuration (adaptedWindow);
-          px_per_sec_ = conformMetricToWindow (pxWidth);
           ensureInvariants (pxWidth);
         }
       
@@ -1020,7 +1019,6 @@ namespace model {
           establishWindowDuration (duration);
           startAll_ = min (startAll_, startWin_);
           afterAll_ = max (afterAll_, afterWin_);
-          px_per_sec_ = conformMetricToWindow (px);
           ensureInvariants (px);
         }
       
diff --git a/tests/basics/time/time-value-test.cpp b/tests/basics/time/time-value-test.cpp
index a3c611c7d..da537a1b7 100644
--- a/tests/basics/time/time-value-test.cpp
+++ b/tests/basics/time/time-value-test.cpp
@@ -312,6 +312,16 @@ namespace test{
           CHECK (         Offset{Time::MAX + Duration::MAX}  ==  Duration::MAX); // clipped at max
           CHECK (         Offset{Time::MIN - Duration::MAX}  == -Duration::MAX); // clipped at min
           CHECK (Duration{Offset{Time::MIN - Duration::MAX}} ==  Duration::MAX); // duration is absolute
+          
+          CHECK (TimeSpan(Time::MIN, Time::MAX) == TimeSpan(Time::MAX, Time::MIN));
+          CHECK (TimeSpan(Time::MAX, Duration::MAX).start()    == Time::MAX);
+          CHECK (TimeSpan(Time::MAX, Duration::MAX).end()      == Time::MAX + Duration::MAX); // note: end() can yield value beyond [Time::MIN...Time::MAX]
+          CHECK (TimeSpan(Time::MAX, Duration::MAX).duration() == Duration::MAX);
+          CHECK (TimeSpan(Time::MAX, Duration::MAX).conform()  == TimeSpan(Time::MIN,Duration::MAX));
+          CHECK (TimeSpan(Time::MAX, Offset(FSecs(-1)))        == TimeSpan(Time::MAX-Offset(FSecs(1)), FSecs(1)));
+          CHECK (TimeSpan(Time::MAX, FSecs(5)).start()         == Time::MAX);
+          CHECK (TimeSpan(Time::MAX, FSecs(5)).duration()      == Duration(FSecs(5)));
+          CHECK (TimeSpan(Time::MAX, FSecs(5)).conform()       == TimeSpan(Time::MAX-Offset(FSecs(5)), FSecs(5)));
         }
       
       
@@ -368,9 +378,9 @@ namespace test{
       compareTimeSpan (Time const& org)
         {
           TimeSpan span1 (org, org+org);                  // using the distance between start and end point
-          TimeSpan span2 (org, Offset(org, Time::ZERO));  // note: the offset is taken absolute, as Duration
+          TimeSpan span2 (org+org, org);                  // note: TimeSpan is oriented automatically
           TimeSpan span3 (org, FSecs(5,2));               // Duration given explicitly, in seconds
-          TimeSpan span4 (org, FSecs(5,-2));              // again: the Duration is taken absolute
+          TimeSpan span4 (org, FSecs(5,-2));              // note: fractional seconds taken absolute, as Duration
           
           CHECK (span1 == span2);
           CHECK (span2 == span1);
@@ -386,8 +396,7 @@ namespace test{
           CHECK (span2 != span4);
           CHECK (span4 != span2);
           
-          // especially note that creating a TimeSpan
-          // based on offset will take the offset absolute
+          // note that TimeSpan is oriented at creation
           CHECK (span1.end() == span2.end());
           CHECK (span3.end() == span4.end());
           
diff --git a/tests/stage/model/zoom-window-test.cpp b/tests/stage/model/zoom-window-test.cpp
index c1f6f38bc..6b02e5591 100644
--- a/tests/stage/model/zoom-window-test.cpp
+++ b/tests/stage/model/zoom-window-test.cpp
@@ -94,6 +94,8 @@ namespace test {
           safeguard_extremeZoomOut();
           safeguard_extremeTimePos();
           safeguard_extremeOffset();
+          safeguard_verySmall();
+          safeguard_veryDeep();
         }
       
       
@@ -523,7 +525,7 @@ namespace test {
           ZoomWindow win{1};
           win.setVisibleDuration(Duration{FSecs(1,25)});
           win.setOverallRange(TimeSpan(_t(10), _t(0)));                          // set an "reversed" overall time range
-          CHECK (win.overallSpan() == TimeSpan(_t(10), _t(20)));                 // range has been flipped forward
+          CHECK (win.overallSpan() == TimeSpan(_t(0), _t(10)));                  // range has been oriented forward
           CHECK (win.visible().duration() == Time(40,0));
           CHECK (win.px_per_sec() == 25);
           CHECK (win.pxWidth() == 1);
@@ -652,7 +654,7 @@ namespace test {
           CHECK (win.pxWidth() == 575);
           
           
-          win.setOverallStart(Time::MAX - TimeValue(23));                        // preparation for Test-4 : shift canvas to end of time
+          win.setOverallRange(TimeSpan{Time::MAX, Offset{TimeValue(23)}});       // preparation for Test-4 : shift canvas to end of time
           CHECK (win.overallSpan() == win.visible());                            // consequence: window has been capped to canvas size
           CHECK (win.overallSpan().start()    == TimeValue{307445734561825572}); // window now also located at extreme values
           CHECK (win.overallSpan().end()      == TimeValue{307445734561825860});
@@ -784,19 +786,29 @@ namespace test {
         }
       
       
-      /** @test verify ZoomWindow code can navigate extremal time positions.
+      /** @test verify ZoomWindow code can navigate extremal time positions,
+       *        thereby observing domain bounds without numeric wrap.
        */
       void
       safeguard_extremeTimePos()
         {
+          ZoomWindow win{559, TimeSpan{Time::MAX, Duration{TimeValue(3)}}};      // setup a very small window clinging to Time::MAX
+          CHECK (win.visible().duration() == TimeValue(280));                    // duration expanded due to MAX_ZOOM limit
+          CHECK (win.visible().start() == TimeValue(307445734561825580));        // and properly oriented and aligned within domain
+          CHECK (win.visible().end()   == TimeValue(307445734561825860));
+          CHECK (win.visible().end()   == Time::MAX);
+          CHECK (win.visible() == win.overallSpan());
+          CHECK (win.px_per_sec() == 559_r/280*Time::SCALE);
+          CHECK (win.px_per_sec() == 13975000_r/7);
+          CHECK (win.pxWidth() == 559);
+          
 //            SHOW_EXPR(win.overallSpan());
 //            SHOW_EXPR(_raw(win.overallSpan().duration()));
 //            SHOW_EXPR(_raw(win.visible().duration()));
+//            SHOW_EXPR(_raw(win.visible().start()));
+//            SHOW_EXPR(_raw(win.visible().end()));
 //            SHOW_EXPR(win.px_per_sec());
 //            SHOW_EXPR(win.pxWidth());
-//            CHECK (win.visible()     == TimeSpan(_t(0), _t(23)));
-//            CHECK (win.px_per_sec()  == 25);
-//            CHECK (win.pxWidth()     == 575);
         }
       
       
@@ -805,6 +817,43 @@ namespace test {
       void
       safeguard_extremeOffset()
         {
+//            SHOW_EXPR(win.overallSpan());
+//            SHOW_EXPR(_raw(win.overallSpan().duration()));
+//            SHOW_EXPR(_raw(win.visible().duration()));
+//            SHOW_EXPR(_raw(win.visible().start()));
+//            SHOW_EXPR(_raw(win.visible().end()));
+//            SHOW_EXPR(win.px_per_sec());
+//            SHOW_EXPR(win.pxWidth());
+        }
+      
+      
+      /** @test verify ZoomWindow can handle excessively small windows.
+       */
+      void
+      safeguard_verySmall()
+        {
+//            SHOW_EXPR(win.overallSpan());
+//            SHOW_EXPR(_raw(win.overallSpan().duration()));
+//            SHOW_EXPR(_raw(win.visible().duration()));
+//            SHOW_EXPR(_raw(win.visible().start()));
+//            SHOW_EXPR(_raw(win.visible().end()));
+//            SHOW_EXPR(win.px_per_sec());
+//            SHOW_EXPR(win.pxWidth());
+        }
+      
+      
+      /** @test verify ZoomWindow and handle extreme zoom-in.
+       */
+      void
+      safeguard_veryDeep()
+        {
+//            SHOW_EXPR(win.overallSpan());
+//            SHOW_EXPR(_raw(win.overallSpan().duration()));
+//            SHOW_EXPR(_raw(win.visible().duration()));
+//            SHOW_EXPR(_raw(win.visible().start()));
+//            SHOW_EXPR(_raw(win.visible().end()));
+//            SHOW_EXPR(win.px_per_sec());
+//            SHOW_EXPR(win.pxWidth());
         }
     };
   
diff --git a/wiki/thinkPad.ichthyo.mm b/wiki/thinkPad.ichthyo.mm
index 14f856604..00476d992 100644
--- a/wiki/thinkPad.ichthyo.mm
+++ b/wiki/thinkPad.ichthyo.mm
@@ -39541,11 +39541,21 @@
 <node COLOR="#338800" CREATED="1668212345981" ID="ID_1473341053" MODIFIED="1668212365788" TEXT="leer konstruiert &#x27f9; default-canvas">
 <icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668180016155" ID="ID_506165727" MODIFIED="1668180136076" TEXT="leere Intervalle">
-<icon BUILTIN="flag-yellow"/>
+<node COLOR="#338800" CREATED="1668180016155" ID="ID_506165727" MODIFIED="1670961012384" TEXT="leere Intervalle">
+<icon BUILTIN="button_ok"/>
+<node COLOR="#338800" CREATED="1670960970348" ID="ID_1737770423" MODIFIED="1670982893953" TEXT="leerer TimeSpan &#x27f9; ensureNonEmpty()">
+<icon BUILTIN="button_ok"/>
 </node>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668180071412" ID="ID_1188877277" MODIFIED="1668180136076" TEXT="falsch orientierte Intervalle">
-<icon BUILTIN="flag-yellow"/>
+<node COLOR="#338800" CREATED="1670960996683" ID="ID_200537694" MODIFIED="1670961014742" TEXT="mutateDuration ist abgesichert">
+<icon BUILTIN="button_ok"/>
+</node>
+<node COLOR="#338800" CREATED="1670961004168" ID="ID_1406068671" MODIFIED="1670961037304" TEXT="calibrateExtension ist abgesichert">
+<font NAME="SansSerif" SIZE="12"/>
+<icon BUILTIN="button_ok"/>
+</node>
+</node>
+<node COLOR="#338800" CREATED="1668180071412" ID="ID_1188877277" MODIFIED="1670961056848" TEXT="falsch orientierte Intervalle">
+<icon BUILTIN="button_ok"/>
 <node CREATED="1668262916332" ID="ID_670540657" MODIFIED="1668262927471" TEXT="weitgehend unm&#xf6;glich">
 <icon BUILTIN="idea"/>
 </node>
@@ -39559,14 +39569,20 @@
 <icon BUILTIN="idea"/>
 </node>
 </node>
-<node CREATED="1668262940706" ID="ID_1639008148" MODIFIED="1668262957124" TEXT="&#x27f9; Eingangs-Checks vereinfachen"/>
+<node COLOR="#338800" CREATED="1670966291514" ID="ID_248415571" MODIFIED="1670982882510" TEXT="TimeSpan::conform()">
+<icon BUILTIN="button_ok"/>
+<node CREATED="1670966626174" ID="ID_1602981358" MODIFIED="1670966640064" TEXT="wird normalerweise nicht automatisch aufgerufen"/>
+<node CREATED="1670966647403" ID="ID_1992293509" MODIFIED="1670966667911" TEXT="kann aber das Schieben + Kappen eines Intervals auf Dom&#xe4;ne erledigen"/>
+<node CREATED="1670966669608" ID="ID_1330290323" MODIFIED="1670966686260" TEXT="erzeugt eine konditionierte Kopie"/>
+</node>
+<node COLOR="#338800" CREATED="1668262940706" ID="ID_1639008148" MODIFIED="1670961054485" TEXT="&#x27f9; Eingangs-Checks vereinfachen"/>
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668554856002" ID="ID_1728331882" MODIFIED="1668554864730" TEXT="potentiell sch&#xe4;dliche Eingabedaten">
 <icon BUILTIN="flag-yellow"/>
 <node BACKGROUND_COLOR="#eef0c5" COLOR="#990000" CREATED="1668262961151" ID="ID_1262854527" MODIFIED="1668270708694" TEXT="alle Eing&#xe4;nge daraufhin pr&#xfc;fen">
 <icon BUILTIN="pencil"/>
 <node CREATED="1668263281549" ID="ID_1653448250" MODIFIED="1668263292760" TEXT="potentiell gef&#xe4;hrlich">
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668263300631" ID="ID_1173749705" MODIFIED="1668265511790" TEXT="setMetric (Rat px_per_sec)">
+<node COLOR="#435e98" CREATED="1668263300631" ID="ID_1173749705" MODIFIED="1670960741915" TEXT="setMetric (Rat px_per_sec)">
 <arrowlink COLOR="#aa6877" DESTINATION="ID_1257614207" ENDARROW="Default" ENDINCLINATION="271;-11;" ID="Arrow_ID_292335664" STARTARROW="None" STARTINCLINATION="314;29;"/>
 <icon BUILTIN="messagebox_warning"/>
 </node>
@@ -39653,10 +39669,19 @@
 </node>
 <node COLOR="#435e98" CREATED="1668269838609" ID="ID_982888658" MODIFIED="1670608801375" TEXT="geeignet normieren oder kappen?">
 <icon BUILTIN="help"/>
-<node CREATED="1670608693763" ID="ID_1403342865" MODIFIED="1670608757928" TEXT="genauere Betrachtung zeigt: hier keine Gefahr">
-<arrowlink COLOR="#7bb8a2" DESTINATION="ID_1497381497" ENDARROW="Default" ENDINCLINATION="-341;0;" ID="Arrow_ID_301661313" STARTARROW="None" STARTINCLINATION="584;36;"/>
+<node CREATED="1670608693763" ID="ID_1403342865" MODIFIED="1670608757928" TEXT="genauere Betrachtung zeigt: hier keine Gefahr"/>
+<node CREATED="1670608703396" ID="ID_1449271152" MODIFIED="1670960623932" TEXT="Duration wird errechnet und ist daher ggfs. sehr gro&#xdf;, aber nicht giftig">
+<richcontent TYPE="NOTE"><html>
+  <head>
+    
+  </head>
+  <body>
+    <p>
+      der Nenner ist limitiert (kleiner Time::SCALE) und nicht toxisch
+    </p>
+  </body>
+</html></richcontent>
 </node>
-<node CREATED="1670608703396" ID="ID_1449271152" MODIFIED="1670608722973" TEXT="Duration wird errechnet und ist daher ggfs. sehr gro&#xdf;, aber nicht giftig"/>
 <node CREATED="1670608782329" ID="ID_1737555624" MODIFIED="1670608799171" TEXT="Pixel-Zahl wird grade hier explizit gekappt"/>
 </node>
 </node>
@@ -39664,7 +39689,7 @@
 <arrowlink COLOR="#bf0f5b" DESTINATION="ID_1671513743" ENDARROW="Default" ENDINCLINATION="297;-23;" ID="Arrow_ID_389982782" STARTARROW="None" STARTINCLINATION="-323;20;"/>
 <arrowlink COLOR="#856e9e" DESTINATION="ID_773636992" ENDARROW="Default" ENDINCLINATION="138;-8;" ID="Arrow_ID_976571904" STARTARROW="None" STARTINCLINATION="219;13;"/>
 <arrowlink COLOR="#65253d" DESTINATION="ID_1915595988" ENDARROW="Default" ENDINCLINATION="9;-40;" ID="Arrow_ID_382076752" STARTARROW="None" STARTINCLINATION="-11;29;"/>
-<linktarget COLOR="#965e8b" DESTINATION="ID_1175951405" ENDARROW="Default" ENDINCLINATION="253;-8;" ID="Arrow_ID_354964355" SOURCE="ID_909162669" STARTARROW="None" STARTINCLINATION="302;-12;"/>
+<linktarget COLOR="#6f4b85" DESTINATION="ID_1175951405" ENDARROW="Default" ENDINCLINATION="300;0;" ID="Arrow_ID_739178440" SOURCE="ID_1976979366" STARTARROW="None" STARTINCLINATION="45;-137;"/>
 <icon BUILTIN="button_ok"/>
 <node BACKGROUND_COLOR="#fefc4e" COLOR="#351d75" CREATED="1668555596031" HGAP="151" ID="ID_1196389964" MODIFIED="1668555795593" TEXT="&#xd83e;&#xdc46; die zentrale Gelenkstelle" VSHIFT="4">
 <edge COLOR="#fdf7a5" STYLE="linear"/>
@@ -39709,6 +39734,7 @@
 <node COLOR="#338800" CREATED="1668703200176" ID="ID_1915595988" MODIFIED="1670608657540" TEXT="conformMetricToWindow()">
 <linktarget COLOR="#65253d" DESTINATION="ID_1915595988" ENDARROW="Default" ENDINCLINATION="9;-40;" ID="Arrow_ID_382076752" SOURCE="ID_1175951405" STARTARROW="None" STARTINCLINATION="-11;29;"/>
 <linktarget COLOR="#6a6a92" DESTINATION="ID_1915595988" ENDARROW="Default" ENDINCLINATION="37;170;" ID="Arrow_ID_1959668732" SOURCE="ID_4317582" STARTARROW="None" STARTINCLINATION="-243;-9;"/>
+<linktarget COLOR="#6a6a92" DESTINATION="ID_1915595988" ENDARROW="Default" ENDINCLINATION="45;199;" ID="Arrow_ID_1858388760" SOURCE="ID_538384824" STARTARROW="None" STARTINCLINATION="-486;-28;"/>
 <icon BUILTIN="button_ok"/>
 <node BACKGROUND_COLOR="#fdfdcf" COLOR="#ff0000" CREATED="1668703282413" ID="ID_1976673029" MODIFIED="1669473783896" TEXT="Output mu&#xdf; entgiftet werden">
 <edge COLOR="#f74141" STYLE="linear"/>
@@ -39750,7 +39776,7 @@
 </node>
 <node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668263629246" ID="ID_1257614207" MODIFIED="1668265511791" TEXT="mutateScale (Rat changedMetric)">
 <arrowlink COLOR="#e62f5c" DESTINATION="ID_651838862" ENDARROW="Default" ENDINCLINATION="115;-4;" ID="Arrow_ID_1930230162" STARTARROW="None" STARTINCLINATION="-189;14;"/>
-<arrowlink COLOR="#6568c0" DESTINATION="ID_909162669" ENDARROW="Default" ENDINCLINATION="-5;-8;" ID="Arrow_ID_1791222915" STARTARROW="None" STARTINCLINATION="-21;18;"/>
+<arrowlink COLOR="#753c82" DESTINATION="ID_1976979366" ENDARROW="Default" ENDINCLINATION="-43;-3;" ID="Arrow_ID_226790124" STARTARROW="None" STARTINCLINATION="80;7;"/>
 <linktarget COLOR="#aa6877" DESTINATION="ID_1257614207" ENDARROW="Default" ENDINCLINATION="271;-11;" ID="Arrow_ID_292335664" SOURCE="ID_1173749705" STARTARROW="None" STARTINCLINATION="314;29;"/>
 <icon BUILTIN="flag-yellow"/>
 <node COLOR="#435e98" CREATED="1668265021139" HGAP="52" ID="ID_1943948610" MODIFIED="1670517343960" TEXT="pr&#xfc;fen: sehr kleine Metrik" VSHIFT="-2">
@@ -39812,40 +39838,11 @@
 </node>
 </node>
 </node>
-<node COLOR="#435e98" CREATED="1668784031268" ID="ID_1513611206" MODIFIED="1670608646043" TEXT="die bestehende Duration k&#xf6;nnte sehr gro&#xdf; sein">
-<icon BUILTIN="messagebox_warning"/>
-<node COLOR="#435e98" CREATED="1668784196906" ID="ID_1074723893" MODIFIED="1670608369272" TEXT="mit dem Nenner des changeFactor bereis &#xdc;berlauf m&#xf6;glich">
-<icon BUILTIN="messagebox_warning"/>
-<node COLOR="#338800" CREATED="1670608372852" ID="ID_110351902" MODIFIED="1670608389199" TEXT="diese Gefahr nun durch Konvention gebannt">
-<icon BUILTIN="yes"/>
 </node>
-<node CREATED="1670608390801" ID="ID_1235208681" MODIFIED="1670608405664" TEXT="die changedMetric wird entgiftet"/>
-<node CREATED="1670608406491" ID="ID_839442543" MODIFIED="1670608429101" TEXT="die etablierte Metrik wird stets in der Berechnung entgiftet"/>
-<node CREATED="1670608433666" ID="ID_1742946325" MODIFIED="1670608454073" TEXT="die Pixel-Zahl ist auch beschr&#xe4;nkt, damit sind auch die Z&#xe4;hler beschr&#xe4;nkt"/>
-<node CREATED="1670608484281" ID="ID_368230032" MODIFIED="1670608495227" TEXT="au&#xdf;derdem ist die Metrik nun nach oben wie nach unten limitiert"/>
-</node>
-<node COLOR="#435e98" CREATED="1668784229969" ID="ID_1956828761" MODIFIED="1670608513302" TEXT="neu errechnete Duration k&#xf6;nnte toxisch sein">
-<icon BUILTIN="messagebox_warning"/>
-<node CREATED="1668784295985" ID="ID_1396219141" MODIFIED="1668784307787" TEXT="Rechnung in mutateDuration() k&#xf6;nnte entgleisen"/>
-<node CREATED="1668784318075" ID="ID_901869945" MODIFIED="1668784338191" TEXT="wird alles zwar in conformWindowToMetric(changed) aufgefangen..."/>
-<node CREATED="1668784339323" ID="ID_1591426559" MODIFIED="1668784345302" TEXT="..is aber trotzdem falsch"/>
-</node>
-<node COLOR="#338800" CREATED="1670608539818" ID="ID_196272847" MODIFIED="1670608638949" TEXT="Duration wird aus Time-Values berechnet">
-<icon BUILTIN="button_ok"/>
-<node CREATED="1670608554153" ID="ID_1497381497" MODIFIED="1670608748968" TEXT="Konsequenz: der Nenner ist limitiert (kleiner Time::SCALE) und nicht toxisch">
-<linktarget COLOR="#7bb8a2" DESTINATION="ID_1497381497" ENDARROW="Default" ENDINCLINATION="-341;0;" ID="Arrow_ID_301661313" SOURCE="ID_1403342865" STARTARROW="None" STARTINCLINATION="584;36;"/>
-</node>
-<node CREATED="1670608581444" ID="ID_1656731502" MODIFIED="1670608593486" TEXT="daher kann Rat(px) / duration nicht entgleisen"/>
-<node COLOR="#338800" CREATED="1670608611402" ID="ID_1320558101" MODIFIED="1670608633024" TEXT="confirmWindowToMetric und conformMetricToWindow sind abgesichert">
-<icon BUILTIN="button_ok"/>
-</node>
-</node>
-</node>
-</node>
-<node COLOR="#435e98" CREATED="1668263638141" ID="ID_909162669" MODIFIED="1669477898780" TEXT="mutateDuration (FSecs duration, uint px =0)">
-<arrowlink COLOR="#965e8b" DESTINATION="ID_1175951405" ENDARROW="Default" ENDINCLINATION="253;-8;" ID="Arrow_ID_354964355" STARTARROW="None" STARTINCLINATION="302;-12;"/>
-<linktarget COLOR="#6568c0" DESTINATION="ID_909162669" ENDARROW="Default" ENDINCLINATION="-5;-8;" ID="Arrow_ID_1791222915" SOURCE="ID_1257614207" STARTARROW="None" STARTINCLINATION="-21;18;"/>
-<node CREATED="1668270374842" HGAP="21" ID="ID_1976979366" MODIFIED="1668270395644" TEXT="delegiert an conformWindowToMetric(Rat)" VSHIFT="9">
+<node COLOR="#435e98" CREATED="1668263638141" ID="ID_909162669" MODIFIED="1670960651484" TEXT="mutateDuration (FSecs duration, uint px =0)">
+<node CREATED="1668270374842" HGAP="29" ID="ID_1976979366" MODIFIED="1670960723275" TEXT="delegiert an conformWindowToMetric(Rat)" VSHIFT="-13">
+<arrowlink COLOR="#6f4b85" DESTINATION="ID_1175951405" ENDARROW="Default" ENDINCLINATION="300;0;" ID="Arrow_ID_739178440" STARTARROW="None" STARTINCLINATION="45;-137;"/>
+<linktarget COLOR="#753c82" DESTINATION="ID_1976979366" ENDARROW="Default" ENDINCLINATION="-43;-3;" ID="Arrow_ID_226790124" SOURCE="ID_1257614207" STARTARROW="None" STARTINCLINATION="80;7;"/>
 <icon BUILTIN="idea"/>
 </node>
 </node>
@@ -39930,6 +39927,20 @@
 <arrowlink COLOR="#e92c3f" DESTINATION="ID_1689286236" ENDARROW="Default" ENDINCLINATION="82;-4;" ID="Arrow_ID_176217068" STARTARROW="None" STARTINCLINATION="-158;21;"/>
 </node>
 </node>
+<node COLOR="#435e98" CREATED="1669479223678" ID="ID_538384824" MODIFIED="1670960844426" TEXT=" Ausgang durch conformMetricToWindow">
+<richcontent TYPE="NOTE"><html>
+  <head>
+    
+  </head>
+  <body>
+    <p>
+      ...und das betrachte ich als gutm&#252;tig und hinreichend abgesichert...
+    </p>
+  </body>
+</html></richcontent>
+<arrowlink COLOR="#6a6a92" DESTINATION="ID_1915595988" ENDARROW="Default" ENDINCLINATION="45;199;" ID="Arrow_ID_1858388760" STARTARROW="None" STARTINCLINATION="-486;-28;"/>
+<icon BUILTIN="button_ok"/>
+</node>
 </node>
 <node COLOR="#435e98" CREATED="1668263473958" ID="ID_773636992" MODIFIED="1668293112414" TEXT="placeWindowRelativeToAnchor (FSecs duration)">
 <arrowlink COLOR="#b18586" DESTINATION="ID_1671513743" ENDARROW="Default" ENDINCLINATION="256;-19;" ID="Arrow_ID_882084800" STARTARROW="None" STARTINCLINATION="-201;12;"/>
@@ -40024,7 +40035,7 @@
 <node COLOR="#338800" CREATED="1668555028046" ID="ID_660534369" MODIFIED="1670517608516" TEXT="sehr kleine Metrix (&#x2259; exterm zoom-out)">
 <linktarget COLOR="#64bc9c" DESTINATION="ID_660534369" ENDARROW="Default" ENDINCLINATION="227;-218;" ID="Arrow_ID_1983834485" SOURCE="ID_78031576" STARTARROW="None" STARTINCLINATION="-503;36;"/>
 <icon BUILTIN="button_ok"/>
-<node COLOR="#338800" CREATED="1669475559599" ID="ID_460741178" MODIFIED="1670376664053" TEXT="setMetric mit sehr kleinem giftigem Faktor">
+<node COLOR="#338800" CREATED="1669475559599" FOLDED="true" ID="ID_460741178" MODIFIED="1670376664053" TEXT="setMetric mit sehr kleinem giftigem Faktor">
 <icon BUILTIN="button_ok"/>
 <node CREATED="1670283526032" ID="ID_229404798" MODIFIED="1670283558380">
 <richcontent TYPE="NODE"><html>
@@ -40141,7 +40152,7 @@
 <node COLOR="#338800" CREATED="1670376631305" ID="ID_840249575" MODIFIED="1670516765208" TEXT="setMetic ganz knapp unter dem Metrik-Limit">
 <icon BUILTIN="button_ok"/>
 <node CREATED="1670376670692" ID="ID_1841257088" MODIFIED="1670376680228" TEXT="funktioniert an sich genauso gut"/>
-<node COLOR="#435e98" CREATED="1670376680960" ID="ID_620447936" MODIFIED="1670516743330" TEXT="Assertion-Failure">
+<node COLOR="#435e98" CREATED="1670376680960" FOLDED="true" ID="ID_620447936" MODIFIED="1670516743330" TEXT="Assertion-Failure">
 <icon BUILTIN="broken-line"/>
 <node CREATED="1670376702055" ID="ID_1469832654" MODIFIED="1670376729324" TEXT="ENSURE (px_per_sec_&lt;= changedMetric); // bias towards increased window">
 <icon BUILTIN="forward"/>
@@ -40192,7 +40203,7 @@
 <icon BUILTIN="button_ok"/>
 </node>
 </node>
-<node COLOR="#338800" CREATED="1670520735802" ID="ID_208606753" MODIFIED="1670889954683" TEXT="Pixel-Zahl dann extrem vergr&#xf6;&#xdf;ern">
+<node COLOR="#338800" CREATED="1670520735802" FOLDED="true" ID="ID_208606753" MODIFIED="1670889954683" TEXT="Pixel-Zahl dann extrem vergr&#xf6;&#xdf;ern">
 <icon BUILTIN="button_ok"/>
 <node COLOR="#338800" CREATED="1670520761346" ID="ID_159180995" MODIFIED="1670608116400" TEXT="bereits sehr gro&#xdf;es Fenster">
 <icon BUILTIN="button_ok"/>
@@ -40700,7 +40711,7 @@
 <node CREATED="1670642186191" ID="ID_1230929067" MODIFIED="1670642222176" TEXT="Fenster vorher auf Max">
 <icon BUILTIN="info"/>
 </node>
-<node COLOR="#435e98" CREATED="1670642203289" ID="ID_415548658" MODIFIED="1670889812462" TEXT="danach Fenster minimal verkleinert">
+<node COLOR="#435e98" CREATED="1670642203289" FOLDED="true" ID="ID_415548658" MODIFIED="1670889812462" TEXT="danach Fenster minimal verkleinert">
 <icon BUILTIN="broken-line"/>
 <node COLOR="#435e98" CREATED="1670682209051" ID="ID_1053497195" MODIFIED="1670684264281" TEXT="Beobachtung">
 <icon BUILTIN="info"/>
@@ -40733,7 +40744,7 @@
 </node>
 </node>
 </node>
-<node BACKGROUND_COLOR="#e0ceaa" COLOR="#690f14" CREATED="1670684285301" ID="ID_1464666749" MODIFIED="1670684347077" TEXT="Grund ist das nachgeschaltete detox(dur)">
+<node BACKGROUND_COLOR="#e0ceaa" COLOR="#690f14" CREATED="1670684285301" FOLDED="true" ID="ID_1464666749" MODIFIED="1670684347077" TEXT="Grund ist das nachgeschaltete detox(dur)">
 <linktarget COLOR="#ff1900" DESTINATION="ID_1464666749" ENDARROW="Default" ENDINCLINATION="90;-19;" ID="Arrow_ID_1868007293" SOURCE="ID_1333476908" STARTARROW="None" STARTINCLINATION="-100;12;"/>
 <icon BUILTIN="forward"/>
 <node CREATED="1670684550969" ID="ID_880239933" MODIFIED="1670684603143" TEXT="seinerzeit eingef&#xfc;hrt wegen Integer-wrap in der &#xb5;-Tick-Quantisierung"/>
@@ -40875,7 +40886,7 @@
 </node>
 <node COLOR="#435e98" CREATED="1670695220102" ID="ID_389130735" MODIFIED="1670889808508" TEXT="Fazit: das nachgeschaltete detox(dur) kann jetzt gefahrlos wegfallen">
 <icon BUILTIN="forward"/>
-<node COLOR="#435e98" CREATED="1670695711835" ID="ID_180269191" MODIFIED="1670889449190" TEXT="Abweichungen bei den letzten Extrem-Tests">
+<node COLOR="#435e98" CREATED="1670695711835" FOLDED="true" ID="ID_180269191" MODIFIED="1670889449190" TEXT="Abweichungen bei den letzten Extrem-Tests">
 <icon BUILTIN="broken-line"/>
 <node CREATED="1670695786581" ID="ID_1444004105" MODIFIED="1670695788153" TEXT="win.setMetric (1001_r/LIM_HAZARD)"/>
 <node CREATED="1670695791701" ID="ID_1934884504" MODIFIED="1670695802439" TEXT="Duration nur auf den letzten 3 Stellen gr&#xf6;&#xdf;er"/>
@@ -41233,21 +41244,32 @@
 </node>
 </node>
 </node>
-<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1668555072594" ID="ID_742229180" MODIFIED="1669473993488" TEXT="Ansteuern exterm gro&#xdf;er Zeit-Positionen">
+<node BACKGROUND_COLOR="#eef0c5" COLOR="#990000" CREATED="1668555072594" ID="ID_742229180" MODIFIED="1670982967576" TEXT="Ansteuern exterm gro&#xdf;er Zeit-Positionen">
+<icon BUILTIN="pencil"/>
+<node COLOR="#338800" CREATED="1670982930768" ID="ID_1528129980" MODIFIED="1670982944610" TEXT="erzeugen mit Start-Pos == Time::MAX">
+<icon BUILTIN="button_ok"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1669475536331" ID="ID_486161883" MODIFIED="1670982947517" TEXT="setVisiblePos mit extremer Time">
 <icon BUILTIN="flag-yellow"/>
-<node CREATED="1669475536331" ID="ID_486161883" MODIFIED="1669475548565" TEXT="setVisiblePos mit extremer Time"/>
-<node CREATED="1669475549345" ID="ID_234786683" MODIFIED="1669475556499" TEXT="setVisiblePos mit extremem Faktor"/>
+</node>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1669475549345" ID="ID_234786683" MODIFIED="1670982949932" TEXT="setVisiblePos mit extremem Faktor">
+<icon BUILTIN="flag-yellow"/>
+</node>
 <node CREATED="1669479474484" ID="ID_1657847338" MODIFIED="1669479489366" TEXT="alle Mutatoren, die conformWindowToMetric() verwenden">
 <node CREATED="1670520100834" ID="ID_636101408" MODIFIED="1670520114018" TEXT="das sind nicht viele (&#xfc;berraschenderweise)">
+<node CREATED="1670961179624" ID="ID_712008770" MODIFIED="1670961184625" TEXT="mutateScale(Rat)"/>
 <node CREATED="1670520136501" ID="ID_1373384288" MODIFIED="1670520142854" TEXT="mutateDuration(FSecs)"/>
 <node CREATED="1670520143698" ID="ID_113302808" MODIFIED="1670520150597" TEXT="und ensureInvariants()"/>
 </node>
 <node CREATED="1670520153513" ID="ID_574049062" MODIFIED="1670520170810" TEXT="wozu? weil dort das Window anteilig neu positioniert wird"/>
 <node CREATED="1670520176781" ID="ID_171252675" MODIFIED="1670520196129" TEXT="&#x27f9; gef&#xe4;hrlich wenn die bestehende Window-Pos gef&#xe4;hrlich ist"/>
-<node CREATED="1670520232861" ID="ID_1248431637" MODIFIED="1670520238057" TEXT="Szenario">
-<node CREATED="1670520238693" ID="ID_1734279608" MODIFIED="1670520244664" TEXT="sehr kleines Fenster"/>
+<node BACKGROUND_COLOR="#eee5c3" COLOR="#990000" CREATED="1670520232861" ID="ID_1248431637" MODIFIED="1670982957635" TEXT="Szenario">
+<icon BUILTIN="flag-yellow"/>
+<node COLOR="#338800" CREATED="1670520238693" ID="ID_1734279608" MODIFIED="1670982961594" TEXT="sehr kleines Fenster">
+<icon BUILTIN="button_ok"/>
+</node>
 <node CREATED="1670520245444" ID="ID_428615363" MODIFIED="1670520257330" TEXT="fast aber nicht ganz an Time::MIN"/>
-<node CREATED="1670520259018" ID="ID_591142628" MODIFIED="1670520301032" TEXT="vergr&#xf6;&#xdf;ern auf MutatDuration - aWeng"/>
+<node CREATED="1670520259018" ID="ID_591142628" MODIFIED="1670520301032" TEXT="vergr&#xf6;&#xdf;ern auf Duration::MAX - aWeng"/>
 </node>
 </node>
 </node>