Grateful Dead shows are unlike any other experience on the concert circuit today, but not for the reasons you'd think.
Regardless of the band's link to the psychedelic '60s and despite the hippy-ish cast of its following, a Dead concert isn't so much a be-in as it is an in-joke. That is, it's so full of subtle cues and shared references that much of the show, though it means a lot to the faithful, is completely lost on anyone else.
Consequently, it's all but impossible to assess a performance like last night's at the Capital Centre fairly. Look at the music objectively, and you miss most of the what the audience is hearing; describe the events with a fan's subjectivity and you essentially surrender judgment. Neither is a completely satisfactory course.