One thing I've noticed that the video doesn't mention is what it's like to work at a sitting desk after having exclusively stood so long.
My hip flexors aren't used to sitting for more than short intervals, which means I can't work at a sitting desk for a whole day without having hip pain.
This was an issue last year when I did some consulting at a company where they didn't have any standing desks available. (At some companies I've actually started the standing desk trend, but this Major US Cable Company was having none of it).
I'd imagine if you exercised/stretched your lower back and hip flexors regularly (deadlifts and squats) that you would be OK to sit for long periods of time.
I guess I didn't notice any problems with hip flexors when sitting on a few very long flights recently, so maybe you're right.