I have often resisted using the Shapes.AddPicture method, sticking with the deprecated Pictures.Insert method, because with the former you have to specify the dimensions of the picture (i.e. both Height and Width) as well as the location and usually I don’t know them (and can’t be bothered with the code to get them). Unfortunately the Pictures.Insert method gives you no control over whether the image is linked or embedded.
However, this morning I realised that you can avoid this problem by simply passing -1 as the value for both Height and Width! (a real “why the hell didn’t I think of that before?” moment)
So the code is simply:
savewithdocument:=msoCTrue, Left:=0, Top:=0, Width:=-1, Height:=-1