imo, it amounts to revisiting concepts once more general principles are found — and needed. For instance, you learn the alphabet, and it's hard. the order is tricky. the sounds are tricky, etc. but eventually, it get distilled to a pattern. But you still have to start from A to remember what letter 6 is, until you encounter that problem many times, and then the brain creates a 6=F mapping. I think of it in economic terms: when the brain realizes it's cheaper to create a generalization, it does so on the fly, and that generalization takes over the task.

Somtimes it's almost like creating a specialist shard to take over the task. Driving is hard at first, with very high task overload, lots to pay attention to. With practice, it becomes a little automated part of yourself takes care of those tasks while your main general intelligence can do whatever it likes, even as the "driver" deals with seriously difficult tasks.