I freely admit that the majority of my word count over the years has come during things. like Nanowrimo, where the goal is to get the words on the page and silencing your inner editor. I'm currently plugging away at the gap (or Gap, at this point - it's earned the capital letter) in Paranormal Investigations, and part of me really, really wants to go back and edit everything I have before continuing into the breach.
Here's the problem with that approach: I know myself. If I allow myself to go into the Land of the Editor, I may never leave. It will be exceptionally difficult for me to switch back to writing if I try to edit everything first, so I'm forcing myself to keep writing and reminding myself that I can fix it in post.
I'm very grateful for the college education that I had, if for no other reason that that it taught me that if I'm given the chance, I will pick my work to death before moving on with new work. I literally had to have parts of my thesis taken away from me by my advisors so I would leave them alone and work on the next piece.
Basically, I'm just going to keep working on draft zero, and resisting the urge to edit all the things until draft zero is complete. After that, well, I might need help getting myself out of the Land of the Editor, but we'll cross that bridge when I come to it.