In regards to the coaching at the military range, I remember that unqualified or underqualified personel were not able to wear the camo covers on their Kevlars.
This placed some peer pressure on some of the guys. The ones who could not make the standard would walk around with the olive drab kevlars sticking out amongst the group. I have heard of other tricks at the military range such as a big X on the helmet signifying you didnt qualify.
The days of negative reinforcement...