If "the pressure" is the main concern, all involved should try and make your son's experience as pressure-free as possible. Where's all this pressure coming from? Pressure is all in the mind and the perception of the situation can be controlled to a large extent. I hope he moves to varsity, takes no prisoners, and HAS FUN doing it!
"Every normal man must be tempted at times, to spit on his hands, hoist the black flag, and begin slitting throats."
H.L. Mencken