Just one little point on those computer tests....
We had a guy downunder that was a seriously good approach controller of some 20 odd years. He left the organisation for personal reasons and finally after some time wanted to come back.... so the powers at play decided the best thing was to make him sit the ab-initio test.
Well as could you could imagine...he failed hopelessly and was subsequently not offered a job even though they were short!!.......but could he do the job? Bl**dy well.