I’ve always understood that this was a potential danger with pesticides, or at least certain ones (DDT?) People would be exposed to “acceptably” low levels over long periods of time, and it would accumulate in body fat. If an overweight person went on a diet, enough of the pesticides would be released into the blood in a short time to make one very sick, or possibly even very dead.
A more reasonable explanation is that your step dad had personality traits that he could keep in check if he wasn’t drunk or under stress. No need to associate it with some holdover of his drinking.
No, that’s what it is, exactly. A behavioral pattern that did not depend on alcohol to play out. That was my point.
Even if that is a thing, it wouldn’t be something that would impair your driving. If you are driving irresponsibly because your are “dry drunk”, its just dangerous driving.