AbdulAlhazred
Legend
Yeah, and like I said in another post, when we bought the Greyhawk book at the FLGS we naturally assumed that this is exactly what was intended. It was never a perfect picture either. I am looking over Greyhawk, and there's no real way to interpret 'filtch items and pick pockets' as a very 'magical' ability, though the explanatory text is so thin that it is easy enough to squint (all that is said here is literally the above text.) OTOH open locks includes 'foiling magical enclosures', and thieves do have other clearly magical abilities, albeit limited and only at high levels.This is a tangent, but interpreting what's described in OD&D & B/X as the ability to "climb sheer surfaces" as a truly extraordinary/near-superhuman ability, as opposed to the much more limited parameters Gygax laid out in 1E*, is a commonly discussed option in the OSR.
Classically, in pre-3E editions, Thieves famously suck. They have terrible HP, bad attack tables, their skill percentages are poor, and DM advice (like Gary gave in the 1E DMG) and "realistic" interpretations often exacerbate these issues, with multiple skill checks often being called for in a single task (like making someone roll both Find and Remove traps, or multiple Climb Walls checks for a single climb, depending on length), backstab being extremely hard to do and limited to once per fight if you can even manage one.
I think one of the big early OSR blogs, maybe Philotomy's Musings, proposed that one way to make Thieves Not Suck (or at least Suck Less) would be to interpret their abilities as truly preternatural. Anyone can move quietly. If the Thief successfully rolls to Move Silently he is literally silent and unhearable, even by creatures with extraordinary hearing. Anyone can hide behind cover or obstacles. If a Thief succeeds at Hide in Shadows, presuming there is at least low light, she actually vanishes into a shadow. Anyone can climb a wall. A Thief who makes their roll can go up a SHEER wall, even one without handholds detectable by any other character. If you interpret these abilities more generously, and let the Thieves truly be extraordinary within their area of expertise, they can be more worth playing.
(*which example has mostly been followed in later editions)
The point is, the logic was simply that our existing PCs could already hide, climb, etc. effectively as 'ordinary folks' (or better perhaps) and thus thieves really HAD to be praeternaturally gifted for the text to even make sense!