At the least, they're more accurate than atomic clocks - when someone first tried measuring how accurate quasars are by comparing them to an atomic clock, they found that ALL quasars were drifting at the same amount relative to the atomic clock - the drift was the clock, not the quasars.
Do you have a cite for this?
Very few electronic parts will fail to produce light, if biased properly.
I agree, it'd be a good idea to have all of those app notes in one place. You might zip them up into one archive file and upload it to the "Manuals" link at http://www.ko4bb.com/ . (Various people have been stashing EPROM images, useful emails, spreadsheets, and other resources in that directory, not just manuals.)
Jim Williams' first book
Jim Williams' second book
Bob Pease's book
Hans Camenzind's book (an especially-cool book by the designer of the original 555)
Happiness is twin floppies.