Wasn't chopstick etiquette important during the Joseon Dynasty?

I saw a historical post a while ago saying that when an envoy from the northern barbarians was expected to arrive,
ministers urged the King to personally demonstrate his chopstick skills before the envoy to show his dignity.
However, it seems unlikely that the King would have shown his dignity as a monarch of a civilized nation by using "X-shaped" (crossed) chopstick techniques.
I am curious about when and where the standard chopstick etiquette we are being taught today originated.