My favorite Cosby derivative was when Saturday Night Live offered a tape of "The Best of Bill Cosby hosting the Tonight Show", featuring Cosby telling a joke no one gets, Cosby mumbling so badly that no one can understand him, and Cosby telling a story going nowhere.
I recently saw a film of Cosby's first appearance on national TV on the Jack Parr Show. He did his "Noah" routine, which was a breakthrough of sorts, in that he was a minority comedian who was doing material solely about something other than how funny it is to be part of his minority. He did the Noah piece just because it was funny on its own merit. I'd rather see a Cosby retrospective than a reunion show, unless they make it "The Cosbys Visit Gilligan's Island".
And as for Dr. Phil, I still haven't decided if he reminds me more of Dabney Coleman or Gerald McRaney.