> Fritz Renner, Inge Kersbergen, Matt Field, and Jessica Werthmann, for showing that drinking alcohol sometimes improves a person’s ability to speak in a foreign language.

I thought it was common knowledge?

I thought it was common knowledge that it makes you feel like you could speak a foreign language better. I don't think it's that obvious that the improvement would be objective or that others around you would feel the same way about you.

(And of course there's a Ballmer peak in any case.)

Amusingly, the study found the exact opposite!

  Participants who consumed alcohol had significantly better observer-ratings for their Dutch language, specifically better pronunciation, compared with those who did not consume alcohol. However, alcohol had no effect on self-ratings of Dutch language skills.
https://journals.sagepub.com/doi/10.1177/0269881117735687

Lots of science is "common knowledge"! This is one of those things that I'm glad to see confirmed in a study.

Of course! It also makes you wittier, taller, and better looking. Everybody knows that.

Not only you, but also makes people of the opposite sex around you more attractive

https://en.m.wikipedia.org/wiki/Beer_goggles

But now you can put it on wikipedia and cite a proper double-blinded study!

Does this count as evidence for Ballmer Peak?