Good post, yeah there is no way tectonics will result in a 30 foot difference in so short of a timespan, tectonics happen so slowly. Perhaps a 6-8 foot increase in 30 or 40 years, but even that number is pushing it.
I should check that DVD out, would really like to see that. Have you seen the IMAX film Baraka?... it's now on DVD, some just incredible camera work in there, some Tibetan shots too.
I think it was this one, which has three Everest documentaries including the original and lengthy Hillary expedition:
Into the Thin Air of Everest: Mountain of Dreams, Mountain of Doom, 1999