I can't imagine not nodding off if someone launched into exegetical phumphering prior to singing a tune. Unless it's a class, of course, and then phumpher away. I'm doubtful about how much even an author "owns" a work once it's published. The ur-text simply becomes a seed for myriad unique readings & performances, each of which is a collaboration among author, performer, and audience. I certainly wouldn't expect a performer to expostulate on the musical variations from "the original" that s/he's introduced either.