Singer-songwriter Bruce Robison is famous for writing highly intelligent, richly detailed country songs—that happen also to be incredibly sad. (See “Angry All the Time,” by Tim McGraw and Faith Hill, and “Travelin’ Soldier,” by the Chicks.) This week, he focuses on a track that first taught him how emotionally sophisticated country music can be, “Walkin,’” off Willie’s 1974 masterpiece, Phases and Stages...before describing his own Willie tribute song, “What Would Willie Do,” and the weird reception Willie got in Bruce’s hometown, rural Bandera, Texas, when he moved his band and family there after fleeing Nashville in 1971. (Hint: The hippies and rednecks didn’t start getting along until Willie got to Austin a year later.)