Maybe you actually focus too strongly (on too many outside thing) and beer helps you limit your focus to only your task at hand.

I was thinking about that (there were a couple of steemit posts on multitasking recently).

They cited previous research with higher BAC where diminishing returns occur (due to the negative impact of alcohol on cognitive functioning). A little bit of alcohol is seemingly beneficial here, but too much and you lose that benefit.

But no numbers (with error bars) I guess?