The second set of this show has a Dark Star > Wharf Rat > Dark Star sandwich, and this jam segment constitutes a big chuck of the second half of the Dark Star. I guess when taken out of the context of the show labeling it as simply a jam is appropriate, but when you boil it down this is technically Dark Star.
From what I’ve read 2/18/71 was originally slated to be the selection for Three From The Vault, but someone nixed the idea. This was Mickey’s last show with the band until 10/20/74. I think that there was some bad blood between Phil and Mickey around the time Three From The Vault came out and I’ve always wondered if Phil deep-sixed the 18th in favor of the 19th as a slight to Mickey. Of course, this is wild, unsubstantiated conjecture on my part, but it’s something I’ve wondered about. Of course, the entire Port Chester 2/71 run is great and I would love to see a box set of the entire run.
Random side note: The jam segment made it onto this list of the 31 best Dead “jams”.
The main theme devolves into some exploration and before long another theme emerges and Jerry toys with it in much the same was as the previous segment. This one isn’t as coherent as the former and soon dissolves into Dark Star.