its about learning how to win against a certain player that counts. not much of the other stuff means much.
you have to know what he shoots at and what he doesnt. and play accordingly. and what he makes and doesnt. so you know where and what to leave him.
the pros make all kinds of shots most should never attempt unless it make it or lose. yet many still shoot at them. if you dont know what % of the time you will make a certain shot, or he will, you then have no idea of whether you should shoot it or not.
then you are playing blind. as most do, and that applies to your 9 ball game as well.