Every argument doubles as a comedy routine, and Ted plays the straight man beautifully. The episode leans on reruns of earlier moments, which is nostalgic the first time and less so the fourth. A thread left dangling since S02E01 gets tied off at last, neatly enough to make a librarian smile. If this episode had a tagline, it would be "Apart from Leslie's marriage, which is a bloody greeting card of some kind." A comfortable, confident episode.