Going on two years, and thought I would update my experience as it may help someone else down the road.
Again, I am roughly 10 deg abducted on the right foot, and only 4 degrees on the left. If I stand with my feet parallel, my right leg rotates inward to the point that the center of mass of my right knee is way inside of the big toe. Both knees are candidates for knee replacement. I am trying to prolong skiing on my real knees for as long as possible. I am 58 and still ski, and bike at a high level.
I got pretty involved in AT skiing about 25 years ago, and after a week of touring my knees would both swell up like grapefruit. If you are in a skin track, your feet must be parallel, and this forced stance just ate away at my knee cartilage. But alpine skiing didn't bother me much until about 5 years ago. Then two years ago, the right knee had enough of the inward rotation required when skiing very steep terrain (like greater than 40 degrees). That's when I started experimenting with the abducted mount.
I AT skied for a week straight this year with absolutely no swelling, and can go out and charge non stop laps area skiing for 4 hours without huge issues. So maybe I have stumbled onto something worth sharing?
The sweet spot for me is a 2 degree binding cant, and 3 degree abducted mount. I started with center of mass knee measurements, and dropped plumb bobs from that point on my knee, but all that measuring seemed to occur when I was not in a truly natural and 'ready' position. So I bought a bunch of binding cants from Cant Co, and started experimenting. Clicked in and buckled up on my rubber shop floor I can get into a true ski stance, flex into my boots, and roll my skis on edge. It doesn't take much time to get a sense of when you are getting closer to a neutral stance. With multiple pairs of skis with different cants, I could A-B skis and immediately verify what cant I prefered.
But with just binding cants things still weren't right. I felt I needed to be a little over canted to bring my knee out to where it belongs (I think directly over the big toe feels about right), but that put me on my inside edge, and I felt a bind in my knee, and hip. So I let my ski tip abduct until I stood flat on my ski, and measured that angle. Then I mounted my binding abducted to that angle. Nirvana, I never felt so balanced and neutral.
I picked up a new pair of Kendos this year, and thought I would try skiing them with just the binding cants. After about 20,000 vert of all mountain skiing on firm snow, lateral knee pain that I had not experienced for almost two years came right back. Redrilled the Kendos abducted, and all is good again.
So yes, I have a nice quiver of skis with a lot of holes.
Best - Bruno