Davis (or Miles, as the “truly hip” say) at this point of his career pretty much eschewed traditional compositional structure. With a swirling electron shell of sidemen and collaborators—in this performance, angular guitarist Pete Cosey and jazz great, drummer Al Foster—Davis, er, Miles transformed jazz’s parry-and-thrust improvisations into rolling, lava-lamp clouds of mood. Many times, more times than it should have, it all gelled into moments of genius.