Probably... considering the personalities in question—Karlach and Izutsumi are pretty different—I bet they thought it'd be funny.

And yeah, Kanda only told me about it afterwards. It sounds like it happened pretty late Thursday. [a beat] From what I remember of him saying, he said it was both that he was trying to mimic Boothill, and that he couldn't even train with his sword anymore since Boothill didn't know how to use a sword.