Using the word koan is inaccurate. I think Yudkowsky is either trying to do it to associate feelings of mystic power with rationality, or to attack feelings of mystic power by setting up expectations and then destroying those; I don't have any idea which. But it somewhat annoys me. It's not a huge deal, but it's annoying.

The first of those two hypotheses but yes, it's annoying and jarring. I had kind of hoped Eliezer got the mystic zen martial arts nonsense out of his system years ago and could start talking plain sense now.