Lip-synching by the illiterate bass? He does more than lip-sync. Sometimes he listens to the melody in the soprano section and sings it an octave or two down. Other times, He listens to that other bass, the literate one, then follows him. Literally follows, vocally, so he is a split second late. And the bass section is divided between those who follow the literate bass and those who follow the equally loud illiterate one. It makes the bass section rhythm really sloppy, and the director has to call the men out several times in the course of a schedule of rehearsals. I've known the director, during the rehearsal, to look the illiterate bass in the eye and say, in front of the group, "You don't know this music!" Calmly, he says it, but it gets said.