Another pic from this mystery show. I do believe the 6/22/68 date from the site; the estimable Dead Essays says this:
A newspaper review: “”Last weekend’s Grateful Dead concert was a smash. Too bad not everyone knew it. The further the Dead got into their music the quicker some people got out to their cars.” [deadlists]
I believe this photo bears out the review: our heroes have assumed, in Mr. Completely’s wonderful phrasing, Jamming Formation with Lonely Keyboardist (Pigpen is off to the left somewhere), and the crowd is sitting down and bored-seeming. Phoenix, Arizona, not getting the Dead in 1968 sounds right as hell.

Yep, everything gels, OTDIDH has been updated appropriately. History in the making right here in river city. This is getting very close to Actual Research.
I’m ashamed of myself.
Now we need pictures of the expressions on the faces of the crowd 28 minutes into The Eleven.
https://crandall1950syoungculture.files.wordpress.com/2012/02/1950s_school_dance1.jpg
http://www.classichorrorcampaign.com/wp-content/uploads/2013/06/giant-spider-screaming-woman-590×331.jpg
http://www.standbyformindcontrol.com/wp-content/uploads/2014/01/invasion-of-the-body-snatchers-the-township-chase1-500×416.jpg
http://assets1.bigthink.com/system/idea_thumbnails/54029/primary/frankenstein_villagers_big_think.jpg?1389058347
great picture! looks like some kind of Scrum with cop, kid promoter, and Student Body Prez in the background
chixx with headband and pixie coiff look poised to make a move, Mickey?