Bernie Leadon is country rock's No. 1 sideman. He played supporting roles in Hearts and Flowers, Dillard and Clark, the Flying Burrito Brothers, and the Eagles. Leadon left that last beast in 1975. He then teamed up with Michael Georgiades and dropped Natural Progression, an insanely mellow fusion of jazzy folk-rock and California-bred rural pop. Both dudes sound as if they're on the verge of nodding off. This record rules for barefoot walks in warm, spring rains. Try it sometime. Seriously.