I've heard of using Press and Seal for marking designs for quilting, and then quilting through it, but I haven't heard of using it for EPP. Perhaps you use a marker to mark a square the size of the piece you need to fussy cut, and then move the Press and Seal around on the fabric until you see the desired pattern inside the square, then cut? I don't see how this would be easier than cutting a window in a piece of regular paper, except that the Press and Seal adheres to the fabric, so it should stay put while you're cutting. I think there's something I'm missing here...