I've never liked LaRussa, and I'm not a drinker, but the list of MLB managers who (1) reportedly abused alcohol and (2) were extremely successful as managers is long. Joe McCarthy has a good argument as being the best manager ever, and he reportedly was an alcoholic. Goodness, Billy Martin battled the bottle, and virtually everyone else, but he was always a very successful manager, albeit usually only for a short term with each team.