I want* to do iOS development in XCode/IB. I don't really want, for example, my dock spread across two monitors, I want to use one monitor as my main display with the second off to the side for documentation and running the simulator.

No doubt with the thoroughly broken OSX window management the maximise buttons in one or more apps would maximise to some random width that is wider than a single monitor when presented with what appears to the OS to be a double width monitor.

* actually, I'm not sure "want" is the right word, but that is another story