I've played often when drunk. First couple drinks, I make plays that I'm not normally confident enough to make (which is hit or miss if my DM is on or not). Next few drinks my aim drops dramatically, my comms become cluttered and focusing on gamesense becomes difficult. Next few drinks I shut down all comms and fail to play properly at all. Next few (if im still going) I can no longer play competitive at all, and will likely end up in a pub sniping (and missing mostly everything) and thinking I am a god.
All in all, I don't know if i'd reccomend doing it often, or in excess at one time, but it can be pretty fun. Pubs are pretty good if you get in a good community one (like the drunken brawl)