I agree with you, but let's admit that what we're saying is that Xcode window management does, indeed, stink--so badly, in fact, that the only sane way to use it is by itself, in isolation, with no other app on the same desktop. I don't know any other application that I give its own space, but I sure do that for Xcode, just as I did for Project Builder before it. I had hoped that Apple would fix this problem for 10.6, but with the API freeze today, and no improvements to Xcode, I'm not raising my hopes.