Very interesting articles. I backpacked for many years through forest and alpine country, much bushwhacking. The weight carreid by soldiers is twice what I allowed myself, even though I was a strong individual (5'10", 175 lbs, medium frame,muscular, heavy bones). OF course I was doing it for fun. I was always armed with a revolver and an extra cylinder of ammo, other than that carried sleeping bag, sleeping pad, cookset & Optimus 8R, light tent or surplus USMC poncho, extra socks, additional layers, and food plus a small pouch of emergency survival gear. I focused on light weight, except that my clothing gradually evolved into being all wool except for rain shell. I found high quality well broken boots with Vibram sole, good arch flex to work well with a minimum of blisters, blisters increased with steepness of terrain. Later, I wore Raichle Montagnas - they were very good boots, but stiff in the arch, gave blisters on back of heel.
I wore light silk inner socks, heavy wool hiking socks, and combatted blisters at the back of the heel by applying a large Bandaid taped securely using low-friction plastic tape. That kept blisters from forming by reducing friction. I used moleskin to cover already blistered areas with moderate success. Moleskin alone on the heel wouldn't last 2 mi of uphill. I like the idea of toughening with benzoin, but never thought of it.
Boot fit is everything. Good fit will prevent blisters and properly matching boot to terrain (the steeper the climb the stiffer the sole) will make for more secure movement. I could never fully condition my feet against blisters because I could never manage more than 2 or 3 day hikes, due to work pressure (desk job).
For many years I ran 3-5 mi a day 4 days a week, doing 150 pushups in 3 sets and 300 situps in one set every running day. That regime did not properly condition for backpacking, it just kept me from dying on the trail.