Drinking and dancing certainly don't mix!! I can understand beginners doing it to calm the nerves but they do tend to cut down when they become more experienced and gain more confidence.
I don't really get to drink a lot these days because of dancing, but then I can live without it. i don't believe you need to drink to have a good time. It's actually nice waking up in the morning actually being able to remember what a good time you had the night before, and that if anybody was to tell you you were dancing on the tables last night, you'd know they were fibbing!!!
