Replace the not-TODOs with NOTEs.

For example, this TODO:

   //todo: factor this out in case X

…is a NOTE, albeit a gratuitous one.

Because if X ever happens, the note won’t matter anyway, since you will have had to grok all the related code to refactor. You will see this note while you’re refactoring the surrounding code and smirk, “yep, that’s right”, or “no, it doesn’t really fall out that way.” Either way, most TODOs/NOTEs like this just get in the way.