I know smokers who down two packs a day but are average drivers and work full work weeks.
I wouldn’t trust a stoner behind the wheel ever, and I don’t know anyone who smokes more than a joint a weekend capable of a full work week.
On the basis of productivity and public safety, cigarettes win hands down.
That you know of. ;^)
I know several people who smoke pot after work pretty much every night, the same way others relax with a beer or a glass of wine. With a couple of them, it was years before they felt comfortable enough with me to reveal their secret. Many people -- probably some known to you fairly well -- are capable of a full work week who smoke "more than a joint a weekend." It's just that they keep their mouths shut.