Agree with most of the sentiments but to dissuade everyone who failed the tests which, although geared towards finding out aptitude for pilot training, really in my opinion do not do a very good job, would be a hell of a waste!
Let's face it, anyone with reasonable mathematics ability, general common sense and (most importantly) practice can pass the aptitude tests most airlines put you through when going for sponsorship or jobs. The micropat are slightly different, I think, but the vast majority of self-sponsored pilots have been knocked back by the airlines and their tests at least once yet gone on to make good pilots. I, along with virtually every other person on my course thought bugger their selection tests and went through the ab-initio anyway with no great drama. I can only speak for what I have personally seen, but of the people I saw struggling, most just didn't put the graft in, though I grant that unfortunately there will always be people that do work bloody hard and still don't get there through no fault of their own. Would tests pick these people out? I doubt it.
As for testing to see if you will be able to get a job when you leave...again a nice idea, but does it really happen on ability? IMHO being "airline material" is quite a small part of actually getting a job post training. Can you gauge luck and determination in classroom tests?
It would have taken a lot of testing to convince me not to give my ambitions a good go and spend my life saying "what if"...