THE troubled English National Opera plans to sing for its survival with the world premiere of a new opera about lesbian lovers that features nudity and sex. ENO, which is only now emerging from a period of deficits of millions of pounds, is pinning hopes on The Bitter Tears of Petra von Kant, an operatic adaptation of the 1972 film by Rainer Werner Fassbinder, the cult German director. The all-female production tells the story of a fashion designer, von Kant, who develops a crush on Karin, one of her models. It also portrays von Kant’s mistress/slave relationship with her mute...