If that's the goal why don't ask for it directly?
Ask for what directly? If he asked for stimulants that didn't interfere with sleep, he'd get replies suggesting... he look for ones with short half-lives like nicotine and avoid long-acting ones like modafinil. Short half-lives is the governing criterion, so he simply asked for it.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.