The girls had pink-cheeked complexions and tousled hair flowing down their backs—a bunch of young English roses who might have been caught by Julia Margaret Cameron’s camera lens in Victorian times. What they were dressed in were the prettiest and most personal designs that have come from Sarah Burton since she took over as creative director of Alexander McQueen. Gone were the face-obscuring headdresses and ironclad corsets; gone the hobbling platform shoes. “I wanted it to be believable, touchable, soft,” said Burton backstage.