I'd disagree with you on the part about the sipping beer while the womenfolk work, but that could just be my gender bias.
Women do most of the physical labor in agricultural/pastoral, non-industrial countries. Men are "too important" because they can get the paying jobs in town --as drivers, tourist industry workers, etc. When I was in India and Nepal, I saw mostly women doing the bulk of the day-to-day hard physical work. Men would plow the fields with water buffalo, and do roof thatching -- which are sporadic or at least not frequent tasks. The rest of the time they drink tea (or booze), play low-stakes gambling games, run cockfighting matches and enjoy other timekillers between sex, plowing and paying gigs.
"Thank goodness for post-Industrial Western life," she said.
I wouldn't say that the only "secrets" are the ones that we don't know about when it comes to the cogently-developed, integrated system of internal body skills that arose in Asia perhaps largely for martial use. It was not meant for the average Joe as load-bearing is, and I believe that it is also not a spontaneous discovery that others will find on their own, although many discrete initernal body skills, such as the weight-bearing method, have been spontaneous, parallel discoveries in many cultures and places in the world. Given a few millennia, a culture will plumb the depths of any skill that is necessary for its survival. IOW, if you live in a culture where you have to carry heavy loads on your body for long distances, your people will figure out a way, over time, to make that process as efficient as possible. And it will be handed down mother to daughter/father to son. Necessity being the mother of invention.
One problem we Westerners have as a group, is that we are armchair thinkers and mental doers. Many of our amazing inventions involve machinery and electronics to do the work for us. Most of us have lost touch with our bodies as machines that do work, and would not know where to begin to learn to manipulate our internal structure and movement.
So, I think that unlike your round-Earth paradigm, knowledge of how to implement internal skills can make a difference in our post-industrial world, in terms of body efficiency in doing work, if nothing else. In martial arts, I deeply believe in their efficacy, having seen and felt it myself. And heck, I may have to carry propane tanks some day, and I sure would like to do it without getting a hernia. And, I want to go back to Nepal and show those ladies that a Westerner can trot up miles of foothill paths at 12,000', carrying a load of firewood without breaking a sweat.
And, Kevin, if you train in and learn this stuff, maybe you could get a gov't contract to teach soldiers how to carry more weight with greater efficiency so they don't eat and sweat so much. We tax payers will appreciate the savings in food, deoderant and other stuff the military uses by the truckload to fuel its troops.