Um, I like double exposures but not when they're abused into multiexposures. -_- with each extra exposure, you lose more detail. These look really low quality, you should look at Flickr: Ren Rox's Photostream for some really good double exposures!
Good idea. I bet that in person, the prints have more detail than we can see here at web size. If you show these to people with an art background they will probably like them. It's certainly not the same-old same-old now, is it!!??
I think you are onto something. You just need to keep testing and testing until you perfect the math of it. First of all you need to have the faces about the same size within the frame to try and overlap them as best as possible and more contrast and exposure time.
Do you know who Bernd Becher is?.. most people think him and his wife just just plain boring shots of industrial buildings, well they shot everything from the same perspective and size (well as close as possible) I know "yawn, yawn, yawn.." Well because they were so meticulous with their shots IDRIS KHAN was able to do these multiple exposures of their work, kind of like an x-ray, kind of like ... I don't know but pretty cool..
well enough rambling, check it out for yourself.