I think medical science has mis-identified the REAL chemical that makes smokers desperate for a cigarette. It's NOT nicotine! That's why their patches and Big Pharma snake oil products work so badly. If you can vape more and smoke less, when you first switch from smoking to vaping, your body simply cleanses you of the REAL addictive chemical(s), and you are quite happy just vaping.
I notice how very easy it is, as a vaper, not to top up with nicotine when you can't. I just get a vague urge like feeling I'd like a coffee or something like that. Whereas, in the old days, if I couldn't have a cigarette, I would completely crack up, no joking. I would go out of my mind, frantic and violent too.
So for me, something is very wrong with smokers being told it's the nicotine in cigarettes that "addicts" them. Now, as a vaper, if I can't have it, I just wait till I can. No insanity anymore. This alone, scientifically, tells me the "Nicotine Addiction" myth is bullshit.