first impressions of dnd 4; part 2: rules and non-rules
It’s been ages since I played AD&D 1E, so these memories may be a little confused. As I recall, there was no unified skill system. You had such and such percent chance to be able to climb a rope or jump a certain distance, but they were all just table after table of lookup. Every class had its own table for all manner of common things. When I played AD&D, my friends and I had memorized all kinds of tables, or at least the page on which to look. (I seem to recall that an important lookup table is on p. 91 of the 2E PHB.)