While I wasn't getting blackout drunk repeatedly, I definitely had an unhealthy relationship with alcohol, and removing alcohol had enormous positive effects on my cognitive abilities.
I also do a heavy dose of caffeine in the morning.
Funny, but yes... even if I drink more than say... two glasses of wine, I am noticeably less alert, drowsy, and impaired the next day. So, not even "blackout drunk..." Better off waiting for the weekends for any alcohol.
My coordination improved when I quit drinking. I was a fairly heavy drinker, but not nearly to that extent. It used to be that when I dropped something, I would seldom catch it on the way down. Now I often or usually do. I didn't notice a commensurate improvement in code output or quality though, but it could have happened without me noticing.
I also do a heavy dose of caffeine in the morning.