Yup, pretty good summary of it - I had an uncle who was in Digger's category; he'd get work and work very hard for a few months at a time, then he'd f*** off for a few months and live like a fish in a bottle for maybe three months and wash, rinse, repeat. I'd guess you could make an argument for JR being an example of a functional alcoholic since he'd so often have a drink in hand and would probably be slightly buzzed in real life (maybe even fueling his own sociopathy?). But mostly I just assume it was down to ignorance at the time about the harm alcohol did - I mean, no one really reacted over the fact that Swellin' was drinking like a fish when she was pregnant with John Ross; it became an issue when she started embarrassing the family with her antics.