FWIW, since this thread started I enthusiastically tried the brown tape/ glass method, and it certainly makes a very flat print. But I don't much like having to cut off the margins by which I handle the print until it is dry mounted; and I found it pretty tedious having to clean the tape remnants off the glass later. So I have gone back to drying prints face down on plastic mesh screens overnight, then leaving them in a stack under a heavy sheet of glass for a few days. I place a waste print face down on top of the topmost one, and have no sticking problems.