Argh! Pigpen being replaced!

L. Rosley pointed out below that it sounds like TC, not Pigpen, on the organ. I've found out that he was right.

Deadbase X makes this comment on the session: "What's obviously going on is that the rest of the band is teaching T.C. the material. Tom himself has corroborated this."
Listening again, this is indeed blatantly obvious. Pigpen is not on organ, and not at this rehearsal at all. Constanten is running through the songs on organ with the band.
Generally, he doesn't sound very "TC-like" yet since he mostly sticks to basic parts (like that constant Dark Star riff). He often sounds awkward & tentative in his organ playing. Ironically, Pigpen would have played these parts better and more steadily, since he'd been doing them for months! - TC has a distracting tendency to try changing the organ tone, and is uncertain about some of the song progressions.

Since TC didn't join the band until 11/23, clearly the 11/6 date is incorrect. I had this session with the date of 12/10/68, which is more likely to be the true date.
(An alternate option is that TC was on leave from the Air Force in early November and visited the band, and his joining them a few weeks later was planned well in advance, to the extent of having this rehearsal. I think this is unlikely.)

This session is, at least, proof that the Dead DID want that little riff going all through Dark Star at the time. (Garcia even makes sure that TC gets it right, playing through it with him.) It's a measure of Constanten's inventiveness that, though he's a beginner in this session, through the following months he was able to expand his Dark Star part considerably until that riff was finally abandoned.

Aside from rehearsing for Constanten's benefit, the band has much trouble with the Eleven, though it had been in the set all year and they were able to tackle it confidently at live shows!
Garcia briefly sings Lovelight as a warmup. The Dark Star is just a laid-back run-through, and the Stephen>Eleven rehearsal constantly stops & starts as the band discusses the parts (barely audibly), so this is probably not a session you'll want to listen through too often!

I'm pretty sure that track 09 is Billy explaining the part to Mickey, not Jerry explaining to Bill. That's Bill talking and playing the drums, with Mickey emulating his triplet rolls. Bill says, "You come over with your right hand first, Mick," at the end of the track.

I really love listening to the band work stuff out. I love thinking about how much energy they were expending to get things just exactly perfect before getting up on stage for us.

If there are no officially released tracks on your copy, you can post it on lossless legs or dimeadozen for everyone to enjoy.

It's fun to hear the boys in the process of rehearsing or recording.

The Dead were in the studio recording for Aoxomoxoa, but this sounds more like a practice session than a recording section. The vocal is barely audible in this mix, unfortunately.
As with other practice sessions, it’s not as interesting as a real show. The first part of Dark Star is repetitive, but begins to move when Phil starts leading the jam.
Keyboard sounds like Tim Constenten, Pig seems to be absent.
They’re playing the Aoxomoxoa arrangement of St. Steven. Here’ they’re trying to figure out the transition into The Eleven, but of course, they gave up on that for the album.

(By the way, the original mix of Aoxomoxoa, still unavailable, is superior to what we have today. I am fortunate to have found a used copy in a Berkeley record shop in 1979, and in good condition.)

Not on deadlists.
Peace, Bob