Also, to the comment about prepping for the tests, you can do better on an IQ test if prepped too. It's invalidates the test results, but some people have manipulated the system that way.
I wonder what qualifies as prepping, and I wonder how much better one could realistically do. I am thinking of the LSAT here (which is essentially an IQ test). A friend of mine taught an LSAT prep course and after weeks of teaching he was happy if he could increase a student's score by 5 points. I'm sure that at least 3-4 of those points were from confidence and from familiarity with the test procedure. According to him, his students pretty much either got the techniques he taught them to use in figuring out the logic problems (in which case they'd probably have figured it out on their own), or they didn't and no amount of teaching really helped.
