The lovely Sarah Wynter, guest starring in one episode, saves the 2nd season of Conchords from being a total waste of time. Her single episode compares favorably to the first season. But the rest of season two falls flat, despite other notable guest appearances. The songs are much less inventive (with the exception of some songs sung by characters who do not usually sing!), and the humor less surprising.
In retrospect, they should not have tried to make season two so similar to the first season — the Conchords’ world should have been shaken up so there would have been opportunities for new humor.