I've done a bit of research into your #1 and I'm convinced that Herman Miller did not design the Embody's back support with posterior pelvic tilt in mind[0]. I think this is why you see the phenomenon of individual buyers preferring Embody chairs after sitting for a bit in a showroom, using the chair for about a month, and then selling the chair or getting rid of it.
Awhile back I borrowed an Embody for the weekend from a dealer and noticed that after sitting in it for an hour or two my lower back would invariably feel like hell. I tried pretty much everything I could think of, and found two things that helped:
1. Stretching and doing other exercises to change my pelvic tilt from posterior to neutral or anterior.
2. Attaching zipties from the back support to the hole in the bottom middle of the "spine" of the chair. This reduces the pressure of the back support.
I ended up buying a Steelcase Leap v2 due to price, but I'm pretty sure that if I tried hard enough I could get the HM Embody to be the most comfortable chair for my body ergonomically. I think it's just unfortunate that Herman Miller seems to completely ignore this problem since it seems to affect a number of their customers. None of the Herman Miller reps or dealers I've talked to seem to really understand this issue.
Linked is an article about how Herman Miller designed their posturefit system to try to push your hips forward. IIRC the Embody doesn't use the exact same system, but I think that they designed the Embody with similar goals. My theory is that if you have deeply engrained posterior pelvic tilt then the gentle nudging of the back support is completely ineffective at getting you to tilt your hips forward, and only digs into you and causes pain.
Awhile back I borrowed an Embody for the weekend from a dealer and noticed that after sitting in it for an hour or two my lower back would invariably feel like hell. I tried pretty much everything I could think of, and found two things that helped:
1. Stretching and doing other exercises to change my pelvic tilt from posterior to neutral or anterior.
2. Attaching zipties from the back support to the hole in the bottom middle of the "spine" of the chair. This reduces the pressure of the back support.
I ended up buying a Steelcase Leap v2 due to price, but I'm pretty sure that if I tried hard enough I could get the HM Embody to be the most comfortable chair for my body ergonomically. I think it's just unfortunate that Herman Miller seems to completely ignore this problem since it seems to affect a number of their customers. None of the Herman Miller reps or dealers I've talked to seem to really understand this issue.
[0]: http://www.hermanmiller.com/research/solution-essays/the-ben...
Linked is an article about how Herman Miller designed their posturefit system to try to push your hips forward. IIRC the Embody doesn't use the exact same system, but I think that they designed the Embody with similar goals. My theory is that if you have deeply engrained posterior pelvic tilt then the gentle nudging of the back support is completely ineffective at getting you to tilt your hips forward, and only digs into you and causes pain.