Do you have a study that confirms your 'melatonin subtracts an hour' theory you could link to?

Not really, unfortunately, but I do have more than a subjective impression; see http://lesswrong.com/lw/1lt/case_study_melatonin/5w76

You should probably argue that everyone should try using melatonin for a week or so, since the potential gains are large, not that everyone who doesn't use it is being foolish.

Yes, this probably can be expressed nicely as a "value of information" problem. I've done that.