To be properly balanced (and not to fall backwards or forwards),
shouldn't the two torques (referred to the midfoot) be equal and
No. In order for a body to be balanced, the sum of all external torques, including both pure torques and torques resulting from coupled forces, must be zero.
In the case of a human squatting, there are no external pure ...
I would say your assessment is correct. There are a couple of cues that you may find useful. One is the "waiter's bow", with one hand placed on your navel to help push your hips back as you bend forwards. Alternatively you can place your fingers into the crease at the front of your hips, and think about "folding" your body at this point.
I think TravisJ gave a good answer on how to squat but didn't cleared the actual concept of why to externally rotate your knees. now let me give me a disclaimer I am not opposing your knowledge about squatting you are right but I think you don't know the actual cause of externally rotation. This answer is from my personal experience so read it full.
Now to ...
Short answer: you don't actually need to flare your knees out, but what you do need to do is generate torque in your hips which can be accomplished by attempting to rotate forward-facing feet outward ("screwing your feet into the ground") and thinking of this as pointing your knees out is a good physical cue.
Details: The reason you externally ...
One suggestion is to remember your forearms must be perpendicular to the ground, no incline either forward or backwards.
About the change in plane on the top. That's to get full range of movement, if you retain the scapular plane you aren't able to get to full extension of the muscles, which is always what you should aim at.
That website's contention for why a thumbless grip lessens the load on the forearm muscles is that it prevents you from squeezing the bar:
in a thumbless grip, also known as a “false” or “suicide” grip, the
thumb is held under or outside of the bar rather than around the bar.
There is no squeezing involved.
However this absolutely would not apply to any ...
There are no clear edges between "beginner" and "intermediate" and "advanced".
My vague definitions would be these.
"Beginner" = fast progress, light to medium weight, lots of flexibility work needed even to do lifts correctly, lots of accessory lifts to strengthen subsidiary muscles
"Intermediate" = progress ...
I think any answer to this would be highly opinionated. There are very loose definitions of what's considered "beginner", "intermediate", and "advanced" in terms of both programming and in skill.
In terms of programming, I would rate them as such (again. There's no clear-cut definition so it's only my definition):
Beginner - ...