For the $100 or so it will cost you in a new gasket, get your utility knife out and cut the gasket and pop the window out. Otherwise you risk cracking your window trying to salvage a gasket that probably won't seal correctly when you go back to re-install it.
To answer your question, I have not. I figured if I'm going to take it down that far, I'm going to do it right and put in a new gasket and prep the pinch weld. You only want to do this once in your lifetime, unless you're a masochist. In which case, whatever floats your boat.
You don't mention the year or model of your car, but it only cost me $90 for the rear window gasket on my 71' Dart. It fits perfectly and doesn't leak.
