"Good grief, we've even been shushed at the Union Chapel when Spiers & Boden and Faustus were onstage. I'd have thought they were noisy enough to overlook a bit of verbal background explanation . . . "

Hee hee. I was charged recently with taking some new converts to a folk club-ish gig featuring Martin Carthy; one of those at our table was doing this sort of (very quiet) explanation of a particular piece and got sharp looks and shushing from the local worthies. It must have been very galling to the worthies to see Martin come and join us during the interval...