I was likewise present and it was an absolutely fabulous show.  Lisner was a great place to see a concert, and GW attracted its fair share of solid acts.   Remember in those days, there weren't too many concert venues in the District of Columbia, especially after Constitution Hall discontinued rock concerts as a result of a Sly and the Family Stone show.  Among the shows during my 4 years were Joe Cocker, Derek and the Dominos. Pink Floyd, Grand Funk Railroad, BB King, and of course Manfred Mann at the first floor cafeteria in the Student Center.   Who am I forgetting...I bet Poog can help me here.