[masspro]

* “which of the 3 big data structures in this part of the program/function/etc is this int/string key an index into?”

* some arithmetic/geometry problems for example 2D layout where there are several different things that are “an integer number of pixels” but mean wildly different things

In either case it can help pick apart dense code or help stay on track while writing it. It can instead become anti-helpful by causing distraction or increasing the friction to make changes.