Boyhowdy! on learning to do without creature comforts. When I went to Outward Bound 20 years ago we slept just on plastic ground sheets (summer only). Took some getting used to, but once adjusted to, no prob!
Bill, I've read a few dozen posts by you, and you seem to be well-respected for your innovation and real-life putting your walk where your talk is...
Would it be improper to ask that you start that thread? for a serious discussion about not just the gear, but the financial, physical, and psychological sacrifices required to go Sub-5, -3, -2 and -1?
I'm thinking you could lay out a few criteria and conditions (I am doing well to go sub-7 right now, so I'm not an expert---just a learner). Not just *can it be done*, but what are the sacrifices, and what are the key "orthodoxies" that must be challenged? For instance, WRT quality of sleep, quality of nourishment, "pack comfort," gear redundancies, advantages of MYOG vs. purchase of production gear, ROI on light-weight vs. overall comfort/quality of experience (realize subjective, but what might be some experiential mileposts common to each step-change?), etc.
(I know this is a lot, but I'm thinking many voices will chime in and flesh out the criteria and the content.)