The third installment of Road Trips, Vol. 4 -- if there's ever been a more confusingly titled series, it's flown underneath this author's radar -- concentrates on the Grateful Dead's stint at the Denver Coliseum in November 1973. The entirety of their gig on November 21 is here, along with three selections from the previous night. The Dead are in a relaxed, mellow mood, yet they also sound unusually lithe as they concentrate on a set that's heavily weighted toward cowboy songs and folk. The big exception is the "Weather Report Suite" that closes the first set, but even that winding epic benefits from this slyly sinewy attack. The Dead may be taking everything easy -- "Playing in the Band" doesn't rock hard, it descends into jazzy interludes -- but there's strength behind their attack, and that's why this performance is worth hearing.