What happens as you age as a reader? In any activity, experience shifts one’s focus from low level details to higher abstractions. Similarly, a better reader is able to see the structure of the books and no mere lines in the book. He is able to see the sequence in which arguments are presented. Organization becomes one of the observables as one becomes more experienced as a reader.
There is a difference between being taught and learning. While something is being explained to you and is completely intelligible, you are being taught and if you are able to follow, it means you have the ability to be taught. On the other hand, if you can work out details with example that you yourself conjure up. You can make yourself see meaning in the sentences that a few minutes ago where unintelligable, then it means that you know how to learning. You have been learning. Or in some sense, you know how to teach and you can be taught.