Yeah, and that kind of people would still use coffee if it were a Schedule IV substance. And I can see no obvious reason why we are in an optimum, where restricting more or fewer stimulants would both be net negatives. (EDIT Actually, before even finishing to read the post, I thought ‘wow -- if what he says about medical students etc. is right, we might want to restrict caffeine! I know I want to become stronger rather than my competition to become weaker, but I don't know if that applies to others, so...’.)

I have not tried to write a mathematical model (should be reasonably easy), but my intuition tells me that the status quo is an unstable equilibrium. It will likely slide toward more universal acceptance, followed by either legalization or enforced prohibition (like with LSD).