Is prog really dead? Have heavy metal artists completely appropriated the term, which was once synonymous with breakaway experimentalism? Not at all. The booming jam band scene currently enjoys a breadth and depth of musicianship not seen in modern music since the ’70s. If you can stand the occasional cloud of pot smoke and the uninvited affections of gentle people, you might be able to learn a thing or two from a band like Garaj Mahal.