Sometimes, as on "I Won't Be Your Yoko Ono," Williams buries a good idea with the explanation of her intentions in her notes. What the Wesleyan-educated Williams might call her thesis, that trading art for love is a foolish barter, comes across fine without the annotation suggesting that Ono was the brains of the Lennon/Ono unit. Still, Williams' narrator's self-assessment, I could sell your songs to Nike/... For all I know I could save your soul, is terse and witty, the kind of guarded promise one artist should make another. On Green World, an album often too gently performed for its smart lyrics, Williams continues to fulfill her promise with personal songs that illuminate more than just their author.