[nollidge]

> "sheer force" would be twisting the tumbler so hard you break all the pins

That's not how I read it... The best gloss of "sheer" in this context would be "pure", which would mean something like "force, devoid of any other tool or method". Like, "I moved the rock with sheer force" would imply I just pushed it and didn't use a lever or anything.

(You are correct that it's the wrong word choice, of course; the above is not what the author is meaning to say.)