I was a big Art Fern fan (matinee movie guy) and I loved Karnac the Magnificent (a direct steal from Steve Allen's "The Answer Man").
Carson could die on stage better than anyone. The more his material died, the funnier he got. I'm sure his writers threw in a couple of absolute clunkers into every monologue just to allow Johnny to react to them.
My favorite answers:
A. a,b,c,d,e,f,g
Q. What formulas did they try before they discovered Preparation H
A. Miss America
Q. What do we hope the Russians do if they drop the bomb.