Thanks everyone for your responses…as I suspected, my height leads me to a setup that most of you don't seem to need. In an email I asked Joe if he had tested the panel tie-outs for strength, and if he had any suggestions for what to do, or not do, when the winds pick up or when above tree line. Here is what he said (emphasis mine):
I am 5' 9" tall. Like some of the other posters have commented, unless you are tall you really don't need the extra head room.
Staking the walls down to the ground helps keep them firmer so that they don't buffet in the wind.
Using poles would make them even more sturdy in the wind, as long as the stake stays in the ground and the pole doesn't fall over.
We've been doing our tie outs the same way for at least three years now. Honestly no one has ever reported tearing out a wall tie out.
I always have a strip of seam tape on me. I know that if I ever did get a tear it would take a few minutes in the morning to fix. Cuben Fiber is extremely "rip stop" and doesn't shred. More likely, if anything you would get a minor opening / leak at the stitching, or perhaps the loop itself would tear off first. Again, I haven't heard of that happening on a wall tie out.
I'd probably use a combination of carbon stakes, and a couple V stakes. Pile rocks on them when above treeline in the wind.
Since I use Ruta Locura's 9" CF stakes and also carry a couple feet of Cuben repair tape, I guess I'm good :)