Therein lies the rub. It depends a lot on the person. There are tons of tenured professors who kick back and don't do much, and then there are those who can't

Therein lies the rub. It depends a lot on the person. There are tons of tenured professors who kick back and don't do much, and then there are those who can't help but keep working hard. I think the hope is that you will luck into getting some of the latter in your group, so even if training the others might end up a waste, some will end up successful. Kind of like the VC model.