My understanding was that a (very approximate) rule of thumb was that alcohol tends to be served in portions that are appropriate for the 2 drinks an hour rule.

My understanding was that a (very approximate) rule of thumb was that alcohol tends to be served in portions that are appropriate for the 2 drinks an hour rule. That is a bottle of beer, a glass of wine, a shot of vodka, a mixed drink, etc. This seems like it would work as long as you treat all of them as trending towards the middle of the alcohol content scale (i.e. treat Miller Lite and a highly alcoholic cocktail as approximately equivalent to a shot ). On the other hand I don't think it would work if you treated the ends of the scale as the same (i.e. treating Miller Lite and a highly alcoholic cocktail as equivalent).