Good news for a capella crusaders. Benjamin Bagby talks to Leonard Lopate of WNYC about the seamy backstory of Gregorian Chant: more to do with Charlemagne than Pope Gregory — who, according to legend, was supposed to have received the inspiration for the liturgical songs direct from the Holy Spirit — as well as fodder for the “Chant Wars,” and the call for a return to Roman “authenticity” in the face of the multi-culti masses.