Just to answer the other part of your question - yes, it was also his own price guide when first issued in the early 1980s. Obviously, the prices listed are well out of date now, but they will indicate an approximate guide to relative rarities. Factor in though, that fewer people were interested in the minutiae of varieties back then, so if he's listed something at 4 or 5 times the value of the regular issue, it's probably rarer than you would think.