Well I would like to clarify a little. When I did my butt sliding...I landed on my feet and just slid along a bit...then just slowly eased down.
When I actually hit my heel...I was trying to do a PLF...though I landed into the side of a small berm was the reason I hit my heel so hard.
I like the idea of the two stage flare...seems like a good way to slow down and have a softer landing...as long as I remember to finish off the flare before the ground.