John Lennon once described her as "the world's most famous unknown artist: everybody knows her name, but nobody knows what she does." Many people are aware of her art, and her music has always split crowds, from her caterwauling earliest work to her later dance numbers, but how many people have looked at Yoko Ono's decades-spanning career and varied work in total and asked the simple question, "Is it any good?" From her earliest work with the...