I feel the need to butt in a bit here, even though I'm not really involved or interested in this hammock design (I'm perfectly happy with my Speer-type). Reason being, the quote posted here from Youngblood.
IMO, sleeping material should NEVER be non-breathable. Why? Because perspiration, to whatever degree, is how your body regulates its temperature. This is true even in cold weather, and it's impossible to provide the PRECISE amount of insulation you need every time. So what happens in cold weather if you over-insulate a bit? In the middle of the night you get too hot. You sweat, but the sweat can't evaporate properly so you keep sweating. In addition, the moisture builds up inside your non-breathable material. Soon you're overheated to some degree and damp. Then suppose you roll over, move around, or need to go to the bathroom. In the right (or wrong?) conditions, you now have the makings of a hypothermic situation. Not good. On the other hand, if your system breathes properly, you allow your body to properly cool itself AND allow excess moisture to leave. Possible disaster averted.
Anyway. Just my thoughts. The only reason I interjected here is that I'd hate to see people innocently hitting the trail and getting hurt. Just a personal hangup (hey, there's a pun!
) I guess.