Too true but I think it depends on the type of mount being fitted,
My mate Kaya (Yorky AEC) has been running this set up for a couple of years now with no problems and if anyone would test it to its limits im sure he would,
Not sure on specifics from year to year, but as a general rule, all chainstay lengths are the same between frame sizes (certainly are for the '94 Explosif above... all are 16.75")
I have my '91 CinderCone set up as a road rat, and with a 16.9" back end, a 36:11 with a new chain is spot on