I am continuing work on the Historical Needlework Resources pages, I have updated the pages the Middle East, including sections on Coptic, Mamluk and Persian historical embroidery. Please feel free to link to these pages if interested.
Ummm, I have to tell you I work for a range of small museums, so have been trained a fair bit by conservators, who would probably have fits (except maybe the dental floss stuff) about some of your suggestions. :( The way we were taught was similar to the splitting - then we sat there with a very sharp scalpel and just very, very, very carefully cut the backs off. It was always find a mechanical method, never, ever a chemical method, as that could do even more harm. And never, ever to apply heat, as it would hasten the breakdown of photos.Now, on the whole I agree with what Chloe is saying but I would also say that most people who do scrapbooking at doing it for enjoyment and as a hobby and don't have the time or resources to treat their photos at the same level as a professional conservator would.
But your alum sounds very special. :)