I wait as long as I possibly can.
The 3 month window doesn't make that easy, but I've waited days when I've only had a week. I don't revise, revise, revise. I wait, wait, revisereviserevise.
The more distance you can give yourself at any time, the better. A month for a short story is probably ideal. Maybe more.
Another question is, how many times have folks gotten their story back after three months, looked it over and fixed a ton of things?
If they're little things, meh, but the stories I could tell you... like, "Why did I make that decision?" and "I cut 800 words from the story after I got it back."