Well, I was right that my warping would get faster. I noticed after the first 18" or so that I had noticeably quickened. Near the end of the warp I timed myself again and found that it was only taking me 5:15 to do an inch of warp, as opposed to the 7:45 it had taken earlier.
I picked up speed partly because I found a better way of ascertaining how many loops I'd done. It proved impractical for me to count to twelve while I was doing the loops; instead I would stop and check, either by eye or by actually touching the threads, to see if the proper number were there. After I learned the most efficient place to look, I didn't have to touch the threads to count them, which picked me up some speed. I also got better at the peg-wrapping sequence. But mostly I think it was the mood music that helped, since the improvement in speed happened on the first day I began listening to music while working.
I timed how long it took me to advance the warp of the header band: approximately 1:30. I figure I advanced it about once for every six inches of band woven. So if I advanced the band warp about a dozen times that makes 18 minutes of advancing the warp.
I'm going to call that as an overall time of about seven and a half, maybe eight hours to weave the header band all by myself on equipment I'd never used in that way before.
As I was weaving the header band, my gauge slackened just a tiny bit. Where I should have finished with 72 sets of warp bundles, I have only 69. (Surely this number is the Cypriot's way of laughing at me, or perhaps blessing my patron.) That works out to be a sett of 23 ends per inch rather than the 24 I was aiming for, but I don't think that's a problem.
I'm more concerned about possible take-up, but I factored in a 10% take-up in both directions. My other warp-weighted loom experience suggests that there'll be a greater than 10% take-up in the weftwise direction, but I am hoping it won't be greater than 14% because then the garment might be too small to fit properly. And after all, my experience has been with weft yarns that were woolen spun, not worsted spun. As long as I don't get too much draw-in, the take-up shouldn't be a problem. That's what the big beefy Navajo warp singles yarn is for: chunky selvedge reinforcements to keep the web from drawing in markedly. And if the finished piece doesn't have a lot of draw-in and take-up, so much the better; it'll fit a little more graciously that way.