Now Jim....I must ask this questions cause inquiring minds ...well inquire..
Does the ski, wide, fat or skinny know it is wide fat or skinng if it's up on it's steel edge, on the rail, turning in it's natural god given designed radius?
There certainly is more (mm) travel distance edge to edge, and as we discussed turning radius may make a ski more challengeing, ski stiffness, and maybe just how much you drank the night before may all influence the amount of energy needed to put those fatties on higher edge angle.
I'm just not sold on the idea that it's just a fact that fatter skis are harder on the knees when put on high edge angle....maybe when I'm older...much much older.....way older....I mean older than pertrifed wood, I mean almost as old as you Jim.?

Now if only we knew someone who could measure exterted loads on the human anatomy..!
One thing that is quite certain, I didn't buy fat skis (to me that means 98 underfoot)? to use as a high edge angle carving tools. Skiing these fatties with softened tipping for crud and pow is the sweetest thing next to....well.....skii
ng 2 feet of powder....ha...!?

G