Interesting! I too write informal brainstorming notes to myself, and sometimes when I don't want to lose momentum while working on the actual draft, I'll write notes like <improve this to make it half as long and twice as funny>, when I think that the idea is sound, but know that the execution is lacking.
I also tag a lot of the "fussy bits" to clean up later, rather than losing momentum by figuring out every last detail. Things like what model of car a character is driving, how long they've worked somewhere, etc. "Tony got into his XXXCARNAME, and said through the open window, "I've been working for you XXXYEARS - how long is it going to take before you trust me?"
Later I do a search for <bracketed comments> and instances of XX, and then do the requisite cleanup. That helps me maintain consistency.
Another question: do you write sequentially, or do you sometimes skip from one scene or chapter to another, based on what you're in the mood to write?
Thanks for the valuable insight!