Can't say if he can control his drinking, it's possible, you and I do, right? could somebody regain control of drinking after losing control for awhile? Possible, but probably not a good idea, because their thoughts would go back to old ways of thinking, stinkin' thinkin' that is.
Unless..they could socially drink only.
That reminds me of where I draw the separation line, it makes it clearer to me--What "normal" drinker would go off by themselves with a bottle? It's that isolation drinking that seems to be where people cross the line. It's no longer a party, or even a cocktail after work to wind down--it's some dark sad place they go to all by themselves with intoxication. It's escapism. there's a distinction--if we use alcohol to escape, it's a problem.