UPDATE: researcher David Kramer-Smyth spoke with Hadi al-Saadoon, who identified David Kessner as the composer. David Kessner confirms he wrote it, but is not sure if it had a name.
At Jerrybase, we are now calling this "David's Tune (Gm)"
On August 20, 1975 at the Great American Music Hall, and again on August 30, 1975 at the Orphanage, both times with Garcia, the Keith and Donna Band played a funky instrumental number the title of which has eluded me for well over ten years.
Looks like I asked about it five years ago.
Someone must be able to identify this tune.
I post mp3s of the two versions here to aid in that identification.