If you haven't smoked from dawn till dusk day in day out, you can't really say people can achieve responsibility with it.
What I am saying is not to disagree, but to state that if you're a person who ends up smoking 12-16 times a day, there isn't much willpower left to handle anything but immediate responsibilities.
You may not use much, and you may not notice how your pot use affects you. But of you ever end up using more regularly, more pot per unit of time, do not fool yourself and believe it doesn't have its adverse effects.
But if you do really think that pot doesn't really impede your motivation, drive, social life etc., then show yourself. Quit for a while, if you can. If you've been deep enough into the hole, coming out will feel like a constant mental overdrive. I've heard it feels kind of like similar bliss people say they might get from meditation, or if you were under very mild psychedelics. Ideas, people, arts, everything feel more innately interesting. As if depression lifts, and the whole experience of being feels more vibrant or vivid. And slowly but surely it all fades away, if you go back to regular smoking.
Yeah, anecdotes from some other life.