CPUs don't have logic or reason, so it's not a good analogy. E.g. you can replace an infinite set of memories by distilling them into a few bits of knowledge that underpin that given set of experiences.
We aren't trying to understand minds or caches, we're trying to encourage a practice that has little to do with the inner workings of either.
They are a starting point for encoding new knowledge in a custom symbolic language known only to yourself. It is the basis for all learning.
Some other major tools for learning are mnemonics and spaced repetition.