Greg, this is in no way dis-respectful. The older you get, the worse the odds become. It's not discounting whatever you've achieved in your past life. I've known uni grads with masters fail, I've known ex-tradies with year 10 pass (
)
While I'm not sure what the odds are for 42 year olds, there are ATC's on this bulletin board WHO ARE INSTRUCTORS IN THE COLLEGE. They've pretty much seen it all, listen to what they say
P.S. there is not an aptitude test anywhere in the world that is a good predictor. If there was ASA would pay lots of millions for it, a failed ATC trainee costs **** loads of money.