Given two similar people that follow the same study good advice, but one takes coffee (or some other stimulant), the person taking the stimulant will do better.

That the author suggests good study habits doesn't mean people shouldn't take them.

Given the risk of addiction, it is probably especially important to recommend good usage habits.

Coffee is a much less effective stimulant for this purpose than amphetamine or methylphenidate.

My point is just about the different between those using and those not - not the degree. In the long term, more powerful stimulants could prove less effective.

One good reason to legalize stimulants is to let more people experiment with them. It would be great to know that taking amphetamine is actually a bad way to work in the long term.

Either way, I'm more excited about non-stimulant methods of increasing concentration. Stimulants seem zero sum, at best.

I'm not talking about a difference of degree where one stimulant is "more powerful" than the other, but in the nature of the effects. "CNS stimulant" is a very vague term which glosses over really major differences between, say, amphetamine and caffeine.

I'm not sure in what sense you mean "zero sum" but it isn't true of amphetamine in the senses that come to mind.

I can attest to what you're saying. I've taken adderall with a prescription for years. I would be very interested to know what the retention rate is for knowledge gained while taking amphetamines vs stone cold sober. I feel like I have a much better command of the material when I use both methods. It's like an automatic mode of reinforcement. For instance, it helps to imagine each chinese character is some sort of animal, so you remember how to draw it by thinking of a duck with horns, and so on. Adderall, Ritalin, etc. force you to perceive the things you're studying in a different way, and add to your ability to retain them. The mixture of the two methods can take you a lot further than one or the other in my experience.

However, as I commented below, I am skeptical as to how concrete the amphetamine driven associations persist 3-6 months down the line.

I'd love to see a study that examined six month+ retention on amphetamines. Part of the reason I'd love to see that study is that it would have to examine six month+ retention in a control group, too. I suspect we'd all be pretty disappointed by the results. We all "ha ha" about people cramming for the test and then immediately forgetting it all, but I think that we all know that that is actually the normal thing for most people. Putting numbers to that would probably be pretty sobering.

(We've talked a lot on HN about whether it's worth it to go to college. That wouldn't be a half-bad metric to use as part of that decision; do you actually recall stuff from more than three months ago in school? If not, don't spend money on college. Obviously, this is not necessary to live a good life because most people seem to manage without it.)

I have to admit I don't remember a lot of the organic chemistry textbook and AD&D Player's Handbook I inhaled when I was 9 and on Ritalin, but I apparently remembered enough of the book on phone switches that digital logic was always a cinch. But that was 23 years ago. I think even five or ten years later, I remembered quite a lot of it.