I just realized why I get more done on weekends: less email to deal with. And fewer distractions overall.
I also realize that this is an obvious thing. Or should be. But it's not, at least to me. Mostly I'm aware of being able to sit down and write a lot of stuff undisturbed. When I'm focused, I'm not aware of much else.
What I need to do now (and have needed to do for many decades) is get some discipline around not being disturbed. Including by myself. And I'm the worst offender because I'm curious about everything. And I want to hoard links I can get to later, which I rarely do.
But with a book to write, I've gotta do that.