Who cares about his singing? He just doesn't have the ability to create a character on stage, he's a personality, not an actor--same goes for John Stamos, for that matter though at least he's been known to have charisma whereas Broadway sucks all the charisma out of Martin for some reason. Pass.
"Some people can thrive and bloom living life in a living room, that's perfect for some people of one hundred and five. But I at least gotta try, when I think of all the sights that I gotta see, all the places I gotta play, all the things that I gotta be at"