People who play jam up when drunk are probably alcoholics and are drinking all the time. I personally know one player who has Budweiser in his veins instead of blood. You NEVER see him without a beer in his hand, yet he shoots fine, and doesn't act like a wasted weekend teenager would.
I've also heard accounts of world beaters running 100 or more while drunk, and have witnessed myself world class one pocket and straight pool play while the parties were heavily drinking. But these are guys who have a high tolerance for alcohol and are used to it.
If you aren't an alcoholic, and just get drunk on the weekends or occasionally, you shouldn't play pool in that state and expect to play well.