“Puppet Class” is not only Howard Stern’s favorite SNL sketch of all-time, it’s also one of the best. Dark, funny, and wholly original, which is exactly why I didn’t expect a sequel, even with Bill Hader hosting. Herb Welch? Sure. Stefon? Obviously. But not Anthony Peter Coleman, although I’m glad we got one — the world needs more flashbacks with dead puppet stuffing falling like snow.