I don't really see that as a different thing. The docs and comments guide you when it comes to doing maintenance, so it's natural to use them to plan and think about the needed changes. They get updated almost as a side effect.

I guess the mindset I have internalized is that I don't really see doc writing/updating as a separate thing from coding. I do it out of habit and without really being aware of it. Or, more likely, I've just been doing this a very long time and have deeply ingrained habits.