He came on the stage of London's Royal Festival Hall like a subway commuter at rush hour. Briskly threading his way through the orchestra, he plopped down on his chair, tossed a quick glance at the conductor and began to play—so abruptly that he took the audience by surprise. Head bobbing, lips pursed in concentration, he embraced his cello bear-hug fashion and sawed away with the workaday look of a man slicing bread.
But what came out was a freshet of lush sound that exploited the limits of the instrument's capabilities. At 38,...