Well, I agree I was an ass there. When I read your comment I thought you were pushing something in the lines of "well, the problem is simple if you treat it with [insert hight-concept mechanism here]", which always gets a bit on my nerves. You know, like none has thought of the problem domain before? Anyway, I think I might have been mistaken.
Also, I totally see how this is difficult (or maybe even impossible) in X, where the window manager is a separate client and there's no notion of inter-client synchronization. I haven't looked into Wayland enough to see what problems it presents (last time I checked it was in a state of major flux) but here's hoping its design entails a much simpler display model.
