RR
Maybe the person in question should try to reform themselves a bit before going for something which could cost quite a bit of dosh. After all spending money on flight training would be a waste if the 'reformation' is not successful.
Drugs of addiction are usually used by people with an addictive personality and despite best intentions these habits are difficult to reform.
The funny thing about reading this thread is that some people like to compare drugs with alcohol use. Although there may be some (?sound) evidence that being a bit stoned makes you not less safe than someone who is pi$$ed as a fart when it comes to driving, I think that the gold standard has to be for people to be sober when driving their cars or aeroplanes.
Call me old fashioned.
FD