[Klathmon]

I can second this. It's like rubber duck debugging but "past you" is explaining it to "future you" who is in a different mindset.

Most of my biggest breakthroughs have happened because of something like this.

And if you aren't afraid to check these brain dumps into your source control in some kind of notes.md, it can also give you a bit more context on what problems you were facing at that time in the repo's life, and perhaps why you thought the solution at the time was a good one.