Regarding unconscious thinking: I've known for many years that if I'm trying to implement something and what I'm doing just feels wrong and I'm not sure why, it's time to stop and come back first thing in the morning. Sleeping on it engages my back-brain; and invariably the next morning everything makes sense, sometimes immediately, and sometimes with just a small amount of work.

Mind you, the solution I have in mind when I wake isn't necessarily the right one; but I get to the right one pretty quickly.