As the mandolinist in the classic country comedy duo Homer & Jethro, Kenneth Burns was one of the finest instrumentalists of his generation, yet many people never realized that fact. Behind the country hayseed garb, the hick patter, and the outrageous parodies of popular songs, "Jethro" Burns and guitarist Henry "Homer" Haynes were expert jazz musicians whose exaggerated hillbilly appearance and zany sendups of songs belied the cleverness of their comedy and the extraordinarily high quality of their music. From the duo's formation in 1936 to Haynes' death in 1971, Homer & Jeth...