I'm happy to concede your point that it is a rare person indeed who is productive in programming while high, but I don't think that has too much bearing on how

I'm happy to concede your point that it is a rare person indeed who is productive in programming while high, but I don't think that has too much bearing on how many engineers smoke pot in general. I mean, of the thousands of drivers I've met in my life, a vanishingly small percentage of them are skillful drivers while drunk -- doesn't mean they don't drink when not driving, though. Personally, I'm a lot more inclined to light up a doobie when I want to prevent myself from working, and gently force myself to chill out and enjoy the process of making dinner with my wife, or tidying up the garage.