Katherine Soper, winner of the Bruntwood prize, is at the head of a promising group bidding to break down barriersFor any British teenage girl hoping to become a playwright, the chances are at last looking rosy. A series of celebrated female dramatists, including creators of hit plays such as Enron, Chimerica and Posh, are now in effect calling out like sirens: "Come on in, the water is lovely."But exactly how welcom…
