George Thorogood buries some obscure covers in his albums. He turns J. B. Lenoir's '50s blues gem “Mama Talk to Your Daughter” into a gas-guzzling roadhouse rocker and uses Elmore James' jumping “New Hawaiian Boogie” as a launch pad for his searing slide work. “My Friend Robert,” a '70s blues-folk ballad penned by Patrick Sky, showcases Thorogood's deft Delta-style picking on acoustic guitar.