(Photo credit: © Camilla Greenwell/Royal Ballet & Opera) Pinching pitches at an apex, Janáček’s “Jenůfa” scales extremes. The opera tells of sextoness Kostelnička Buryjovka, who takes a lethal misstep to protect her stepdaughter. Persuaded Laca will agree to wed Jenůfa if she’s childless, Kostelnička drowns newborn baby Števa. Rue accrues until Kostelnička confesses. Any other art form would attribute her {…}