Culties in three-part harmony

As if you don't already have enough on your mind when you get on the subway ("Back Bay station is next; please be careful exiting the train - blood is slippery"), now you have to worry about being serenaded by the LaRouche Youth Movement:

Yesterday, a squad of three identically-dressed girls schlepping armloads of leaflets about "The Fraud of Global Warming" methodically worked the cars on an outbound train to Alewife, getting off at each station and reboarding a new car at the next to sing "no more Al Gore" in (admittedly rather lovely) altos. ...