The SAT doesn't actually test anything useful, only your ability to learn the tricks of the test and the language and format of the test, but not the content of the test. You can't have a proficiency test whereon tricks are necessary to score well.
I agree; on any test, it's not so much your understanding but how much material you can cram into your head within a short period of time. It's also dependent on the context of the test, your teacher and how many marks it's worth. I've seen kids who literally understood NOTHING about a subject when asked, but had practically memorized everything and got full marks for it, while another actually intelligent kid basically just said screw it to all the trivial data and statistics.
Nowadays, memory = intelligence, not problem-solving skills.