I had a terrific opportunity to see them in concert. It was sometime around 1979 or '80, and they opened a show that was headlined, I believe, by Frank Zappa...and I think also included John McLaughlin's Mahavishnu Orchestra on the bill! Wotta show! The thing I most recall about GG was that it looked like a Chinese fire drill; every member of the band appeared to be playing no more than two or three bars before switching to a different instrument! Yet the sound was seamless...it was either a case of superb arrangement and "choreography," or some kind of incredible innate display of multitalented professional musicians...or maybe the dope we had that night was better than I recall!