This is not new (2009) but I never saw it before. Quite the Heady read but worth the effort IMHO.
here's an excerpt I liked and the link to the whole essay is below. Enjoy.
Paradoxically, the musical identity subverted by the band’s devotion to internal difference begins to lead back into sameness, and the group’s jams start to resemble one another more as they resemble themselves less. The Grateful Dead always sound different from every other band, but always the same as themselves, even as they seek to play something new every night. Variety in the Grateful Dead’s music is firmly rooted in actual polyphonic texture, not in mere timbral contrast more readily perceived by the listener.
These paradoxes of similarity and difference are evident in the band’s relationship with the “straight” musical world. The Dead borrowed from virtually every genre of American music and have inspired many “tribute” projects and millions of amateur renditions of their music, yet their music cannot be faithfully copied. Due to the absolute impossibility of imitating Lesh’s bass work or the unique interrelationship of the drummers, the unusual guitar styles of Weir and Garcia are by default among the more easily imitated aspects of the band. The Dark Star Orchestra, which specializes in playing set lists of famous Grateful Dead concerts in their entirety, exemplifies this strange paradox. Even if one were to laboriously learn a Lesh bass part note-for-note for a given piece of music, it would be pointless to play it without the rest of the band duplicating their respective parts. But if this were to be attempted, the very spirit of the music would be absolutely undermined.
http://www.popular-musicology-online.co ... .html#fnr5
here's another quicker Phil interview...note the last quote from Phil....
http://www.billboard.com/news/phil-lesh ... 6352.story