But one of the best reminders that comments don't do sh+t was early on in my career when my co worker asked me a question on a line of code (and it was literally just the two of us working on that code base). I probably had a very weird look on my face. I simply pointed to the line above the one he asked about. He read the comment and said "thank you".
I guess my point is that all you can do is to incorporate the "extra information" as closely as possible to the actual code, so that it's less likely to just be ignored/not seen. Thus incorporating it into the variable and function aiming itself is the closest you will get and as per your example (and my own experience as well) it can still happen. Nothing but rigorous code review practices and co workers that care will help with this.
But I think we can all agree (or I hope so at least) that it's better to have your function called `findAllDependents` and be slightly out of date than to have it called `function137` with a big comment on top that explains in 5 lines that it finds the list of all dependents.
Led to a non-obvious bug because from a high level, the code all looked fine, and it was only digging into the dependents code that revealed that not everything was getting returned anymore.