Everything they can do is either not funny or a copy of something another show has already done, and thus not funny. In fact if you click the link and look at the video on the right that is called "The Oates Tour" or something similar, the video is an advertisement for a John Oates tour without Darryl Hall and shows him just playing bass and singing randomly harmonies with no band. Late Night With Conan O'Brien did this around 12 years ago with Max Weinberg selling a CD of Springsteen's hits, with just Max on Drums and no vocals. Additionally, Modern Family, the sitcom, did it last year with Ed Norton guest starring as the Bass player and backup vocalist from Spandau Ballet. Thus, highly unoriginal and not funny. Though I did laugh when the woman went to God to cure our pain.
22 Minutes was good when it was still the original four, just like Air Farce was good up until the night they added Luba Goy to the "Canadian Moment" coffee shop skit ("tell me about it" was the shark jumping moment for me).