I've had to do it many times, both increasing it when words are flowing and decreasing it when life's in the way.

Absolutely. I've heard it said that all writing is revision. Event the first draft is an iteration of what you was in your head before you wrote it down. And there are some things that you can't beat a second set of eyes for.

Yeah, it's a little tricky to balance "keep working" and "don't beat yourself up if you can only work a little bit," but any progress is good progress.

Little things can go a long way to closing the gap between nearly done and completely done. Half of these were reminders to MYSELF to keep doing them.

For me, setting goals and deadlines, and tracking word count have all helped me finish, but I haven't always been as good about tracking plotting, trying out dialogue, voice etc. The same goes for tracking my revision progress--pages or word revised isn't a perfect metric, but it's a useful one.

Your final point, about progress, however incremental, being significant is well worth keeping in mind as we work toward finishing a project, and starting the next.