[dllthomas]

[2b] is to use the type system to make sure the places are consistent, the practicality of which depends significantly on both particular task and choice of technology.

[3b] is adding comments, which is better than relying purely on memory but can often be missed. I've locally improved on this a bit by including cross-references on the relevant lines, along with tooling such that the referents are automatically surfaced during code review.