The grateful dead weren't that great in the late 70's, for the most part. Terrapin Station wasn't much of an album, although it had a lot of good parts. The other albums of the time were kind of hit-and-miss. Apparently though, three shows in spring of '77 are legendary, particularly the versions of peggy-o played on those three occasions. The song is incredibly beautiful and jerry encompasses so much in his voice. I finally located an mp3 of one of those shows. It made me happy.