But here, singing "Mutual Admiration Society" (with some changed lyrics) are Joe E. Ross and Fred Gwynne, as Officers Toody and Muldoon, in the classic sitcom, Car 54, Where Are You?
No, really. Seriously. I'm not kidding.
We dig deep and find the bizarre arcania so's you don't have to.
Joe E. Ross was a longtime nightclub performer, and I will assume that he did some singing in his act. And Fred Gwynne was a respectable singer who, among other things, was in the Broadway musical, Here's Love, by Meredith Willson, based on Miracle on 34th Street.
(I worked with Fred Gwynne on the film, Pet Sematary, and he was a nice fellow. He was quite a good and versatile actor who finally was able to turn his career around after being ignominiously typecast and having it trashed by The Munsters, a subject he pointedly and understandably had no interest in talking about. I politely steered away from it.)
So, here -- in the most unlikeliest of places -- Is yet another version (and oddest) of "Mutual Admiration Society."