The late Michael Rabin was playing a violin concerto in the Robin Hood Dell (which is (was?) Philadelphias outdoor concert hall. When he finished a man shouted over the applause "You are a regular Heifitz!" Someone else yelled, "You are a regular Michael Rabin". I think that was meant to be a compliment.

A friend of mine is a mathematician who plays the guitar. At a conference he gave a talk. That evening after dinner he played his guitar. One courtly colleague said, "I could tell from your talk that you were a musician." Again, I think that was meant to be a compliment.

Murray