This happens to me as well, however, my stutter gets infinitely worse the few days after. I've heard it be called hangxiety (hangover + anxiety), but, whatever it is it makes me feel like I shouldn't have drank so much in the first place. Going from my usually mild stutter, to completely fluid when I'm drunk, to sober and barely able to form a sentence is a wild ride. And if I'm being totally honest, I'm not always 100% fluid when I'm drunk. I'm just so drunk that I don't care if I stutter or have vocal blocks in front of people.