Lukas suggested to not provide backward compatibility and compile 1 at -2
as 1 @- (2)
That's what Igor expect, and that's what VW did.
In my image this would mean changing:

AlignmentMorph>>#addUpDownArrowsFor:
BalloonCanvas>>#makeRoundRectShape:radius:
Cursor class>>#initBottomRight
Cursor class>>#initResizeLeft
Cursor class>>#initNormalWithMask
Cursor class>>#initResizeTopLeft
Cursor class>>#initCorner
Cursor class>>#initCrossHair
Cursor class>>#initSquare
Cursor class>>#initResizeTop
Cursor class>>#initResizeTopRight
Cursor class>>#initBottomLeft
FlapTab>>#fitContents
FontChooserMorph>>#createWindow
Form>>#findShapeAroundSeedBlock:
Form>>#pageImage:at:corner:
Form class>>#xorHack:
Form class>>#toothpaste:
FractionTest>>#testFractionPrinting
GraphicSymbolInstance class>>#example
MethodFinder>>#testRandom
MethodFinder>>#testFromTuple:
Morph>>#changeColorTarget:selector:originalColor:hand:
PNGReadWriterTest>>#drawTransparentStuffOn:
PNGReadWriterTest>>#drawStuffOn:
PaintBoxMorph>>#init4
PaintBoxMorph>>#fixUpColorPicker
PianoKeyboardMorph>>#buildKeyboard
Point>>#fourNeighbors
Point>>#eightNeighbors
PointTest>>#testBearingToPoint
PointTest>>#testTheta
PolygonMorph>>#nudgeForLabel:
PostscriptDummyWarp>>#subCanvas:
PreDebugWindow>>#adjustBookControls
ScriptEditorMorph>>#createThreadShowing
ScriptEditorMorph>>#extent:
ScrollPane>>#vResizeScrollBar
StandardSystemController>>#cursorOnBorder
StandardSystemView>>#closeBoxFrame
StandardSystemView>>#growBoxFrame
SyntaxMorph>>#selectorMenuAsk:
SyntaxMorph>>#drawOn:
SyntaxMorph class>>#standardInset
TTSampleFontMorph>>#drawCharactersOn:
TTSampleStringMorph>>#computeTransform
ViewerLine>>#addGetterFeedback

This would also mean breaking some packages.
One known workaround is to implement @- (main cause of error)

Nicolas