I wouldn't think he's "Mutt or Jeff" or "Mutt 'n' Jeff", he's a muso after all.

To explain the above sentence to non-UK folks which, incidentally, doesn't include Diki, the term "Mutt 'n' Jeff" is cockney rhyming slang for "deaf".

Footnote: Cockney rhyming slang consists of phrases used to mean something different from what is actually said, usually rhyming with the second part of the phrase, as in the above example. Okay, I'll stop here before I become as confused as the rest of you might well be by now.