The answer to the question of how often you can drink without it being detrimental I think entirely depends on how one handles hangovers. When I get trashed, the next day is completely worthless for me, and the fact is that during 1L you really can only completely waste 2 or 3 Saturdays or Sundays a month. If you can get hammered on Friday night, but still be cranking out the work by 2pm the next day, this will be entirely different. Personally, trying to read about personal jurisdiction when I'm hungover makes me vomit. In the end, I'd say I partied hard about 3 times a month during 1L and had a drink or two at dinner maybe 1 night a week. I probably averaged getting loaded 2 times a month during 2L and had 1 or 2 with dinner or before bed 3 times a week, but mostly just because I continued my relaxed 1L drinking habits without really thinking about it. I could have drank more had I wanted to.
...and for Jacy85 and unlvrjchick, why do you assume that law students only go out drinking a lot because they feel like they should be doing what everybody else does? Did it ever occur to you that some people actually enjoy going out and getting loaded? Also, why are people that drink when they want to release stress 'stupid?' It's funny, the word stupid comes to mind for me when I think about people who are self-righteous and feel the need to judge the intelligence of others based on personal choices that don't, at least in and of themselves, harm other people.