Do I daydream?
Yes.
On purpose?
Yes.
Is it a critical part of my writing process?
Yes.
Do I recommend daydreaming to anyone even thinking about writing fiction?
Oh definitely yes.
My favorite ways/places to daydream about my works-in-progress:
1. Whilst walking around my back yard and waiting for dogs to do dog business.
2. Whilst driving.
3. In the shower.
4. Whilst doing dishes.
5. When someone else is talking to me about something important.
6. Pretty much any time I do not have easy access to a notepad or other method of actually documenting the genius ideas I come up with during these daydreaming sessions.
On a slightly more serious note, some of us have these weird writing processes where we think-think-think for like months and then BOOM write a full novel in a couple of weeks. All of that think time could be described as daydreaming, I suppose. It's definitely time I spend putting the story together in my head, and I almost never document all of that work on paper. (Which is why my word-count tracking is super sketchy.) If this is your process or you're thinking about trying it out, stop telling yourself that you have to make a daily word count and get to daydreaming instead. (I know, it sounds miserable, dunnit?)