Thanks for the replies.
Dave O., I have the Rogue Do Wins and the heel does help.
David D., my big problem in the position was losing my balance forward, especially on the recovery. Theres also the issue of effiency, where it is preferable to have your spinal column support the load over your head, especially when the weight gets heavier, vs. the shoulders supporting it in a somewhat compromised position. I'll let the guys who know what they are talking about answer though.
I was messing around today at work, and I can squat w/ an upright spine, so the footwork is another thing I need to work on, hitting the right position to get my butt down on my heels.
I'll post some more videos next Saturday with hopefully some improvements.