This kind of “background processing” was covered in detail in the infamous “Learning how to learn MOOC”. I would go further suggesting that for people unaware of this way of thought processing/problem solving (like OP?) peer pressure may bring something akin to impostor syndrom.

This doesn’t have to be a programmer only thing IMHO. If you spend 5 hours chilling and 3 executing and everybody is happy with your performance, it may be just your way to do things. If someone next to you does the same by coding 8 hour straight - its their style, and neither is better.