'Entertainment' comes in many forms, and I used to rather resent it when asked by folk club organisers who I'd cold-called what my 'patter' was like, as if folk music needed comic monologues to be rendered interesting. Frankie Armstrong tearing the house down with 'Tam Lin' is pretty damned entertaining in my book, if entertainment is allowed to include sitting open-mouthed with your hair standing on end.

That said, I don't generally enjoy serious or po-faced performers unless they're very, very talented (and not always then). A light and informative introduction, though, can definitely count as part of the entertainment in my book.