Interesting points, but I thought that the personality tests were not a part of the selection process?
I guess the point I was trying to make is can it be possible to determine wether someone has the mental capacity to fly airliners by a mere 25 question maths test? Or a twenty five minute english diagnostic check? With only a small amount of time to 'prove yourself worthy' luck must play a dis-proportional role. With longer tests, such as the RAF ones, if twelve minutes of it doesn't go too well you have always got another six hours or so to prove that you actually are capable.