When I am seriously working on a project, I'll continue "working" even when I'm not at my desk. I've called it immersion theory in the past. For several weeks this past month, I was stuck on the same paragraph, which you may remember because I whined about it here. Part of what held me back on that, I'm sure, was that I kept taking time off from work to go here and there and never got immersed in the job.
Last week immersion finally came. Yesterday, an intense housework day for me, an idea came related to a chapter I'd just finished revising. And today, while driving for a couple of hours, I got a big idea for changing a character in that same chapter. I didn't even know there was anything wrong with her. But now I'm sure she's just a dull, hollow shell.
She won't be after tomorrow.
It's good to be immersed.