How does Darmok even count as a "tribute" episode? Sure it was living up to tha standards of the best of Trek (and brilliantly so, IMHO), but that's what the writers tried to make TNG be most of the time anyway. There's certainly no indication that Darmok was intended as anything other than a regular episode of the show, unlike T&T, which was a heavily-hyped "event" episode.
