I appreciate all of the advice. Now I have lots of things to try out. Sounds like before I switch to HB I should tinker with my setup. I use flat clickers because they are easier to get in/out. And very stiff K2 boots. I use power straps as well. They are cranked to the point of preventing circulation, so they are not loose. +30 degrees front, -7 degrees back. Soulder width apart.
As for OffpisteHardboots comment about it not making sence, it probably is my technique. I probably don't bend my knees enough and jaming stuff in the back of my boot forces me to bend my knees. When I turn from heel to toe in the deep stuff, I un-weight the back and try to kick my rear foot back. But I often can't get turned far enough (because I'm pushing snow) and I end up standing up with my legs straight in the middle of a turn, then I have to horse it a round a bit more which can get a bit hairy when you're heading for a tree.
I can carve like a pro on the groomers but powder's another story for me. I actually did make some wedges to put under my clickers but they were too steep. I'll try one just for my back foot and make it less steep. I'll also see if there is a way to move my boot towards the toe edge.