When the couturier Christian Dior died suddenly of a heart attack at 57, a jittery, bespectacled Algerian-born 21-year-old had to put the Dior show together. He came up with the trapeze, a dress that by dint of its intricate silk, tulle and horsehair-hemmed organza underskirts seemed to float away from the body as if by magnetic force. It was a sensation. The fashion press, not given to understatement even in 1958, proclaimed, "Yves Saint Laurent has saved France." A new design legend had arrived.
He left last week, almost as abruptly, making the front pages again, even though his retirement...