Only in the long term. I've used beer before other competitions just to settle my nerves. I used to be a financial advisor, and I acquired many more clients on fridays than any other day, because the office allowed beer on Fridays. Weird, but true.
beer is mostly water. it will hydrate you until you have to pee. Drink a dark beer like stout and you get a LOT of calories AND complex carbs for long term energy AND simple sugars the the yeast left behind for a quick boost of energy.
Alcohol inhibits ADH, and you become dehydrated relative to the amount of it in your system. I can't imagine why anyone would want to drink beer on a ride, or before a ride versus water/juice/sports drink/etc.