I checked out some pictures of Paul Valentine. He was a really good-looking guy back in the late 40's and early 50's. He played Joe Stefanos in the great film noir, Out of the Past. He was gangster Kirk Douglas' enforcer or capo (I guess you could call him), similar to the character of Al Neri in The Godfather. I believe he is the guy on the Wish You Were Here cover. He sings "Summer Afternoon" and "Relax" in the Rome musical.
Thanks for the mention of Oh Captain!. I'm going to dig out the CD and listen to it tomorrow. It has a very enjoyable score with a great cast.