I have always found it hard to believe that not only the Spewacks and Cole Porter, but that no one at all involved with the creation of KMK was familiar with the SUPERMAN comics/radio show/films. Superman was, as you say, not a new thing in 1948. And I'm pretty sure that SOMEONE of the many people involved would have brought it up.
I think it's most likely that someone knew and it was mentioned and an active decision was made to not care and keep the name for the character in KMK. Why? I have no idea. Makes no sense, but, then again, welcome to KISS ME KATE! |