Dakota:
There may be studies, but I am not buying it. I watched many a golfer score just fine, well over .05 BAC...if golf isn't a coordination game, I don't know what is.
They would have scored measurably higher against their own score without the alcohol. That is demonstrated in every study that ever gets done.
Heck, play a video game for score. Drink a couple beers, wait 15 minutes, and play the same game again. It's not hard to prove it to yourself.
To argue against alcohol as an intoxicant at any BAC-level is simply denial of reality due to the chemistry of our bodies. There's no way around it.
Now, whether the govt should be involved in regulating that intoxication is a whole other question.