Chatter rolls with Claude, David, Jamie and Torie. They do “Chatter on Weddings” (they used to be a lot less complicated), contemplate a live show, share father’s day experiences, and somehow veer into what makes elite athletes so dedicated. Karen Valby zooms in from Austin to share “The Swans of Harlem.” Until now, not many outside the world of ballet (heck, even inside that world) knew about five pioneering Black ballerinas and their remarkable friendship that has survived fifty years.