Elvis Costello’s restlessness is often palpable, a sense of unfulfilled musical curiosity that, like the most creatively ambitious artists, sometimes finds his reach exceeding his grasp. Costello has dabbled in everything from jazz to classical forms in recent years, and collaborated with artists as diverse as Bill Frissell, Burt Bacharach, opera singer Anne Sofie von Otter―and of course, his wife and mother of twin sons Dexter and Frank, Diana Krall. ...