Often I will be the driver to/from a venue which places a limit on how much I can drink. If not (or if on a weekender) I do like a pint or two as anyone 'dancing' with me at Biggleswade 2 weeks ago will have noticed
I am not sure that drinking improves your dancing but it certainly makes you feel like you're dancing well even if you're not
The downside is the accelerated dehydration - combined with inadequate cooling at many venues it's a recipe for a nasty day-after.