rom the Hendryx website:
"Duckstance rules! If you have tried it, you´ll never go back! Ask seth Morrison!
Yes, I know there are many of you out there wondering why?
                        
There are actually two reasons for mounting duckstance. The first
one is that this position is a more natural position anatomically. If
standing or walking your feet are naturally pointing outwards. If doing
squats, with weights, you are about 20 percent stronger in duckstance position than if you are pointing your feet straight!
The second advantage is truly when it comes to
skiing technique! Okay, now it becomes a bit more complicated! I
usually tell people that I can´t make a ski that takes your skiing to
heaven but what I have done is that I have made a ski/skis that is standing beyond todays skiers and to make use of them you have to start think of the way you ski! If you do that, then you´r on your way to heaven!
Big point here is to bank your skis equally much and a weight distribution between your skis of 50/50 %!
This is very hard at a normal stance as your knees tend to fall in and
making your inner ski to plough! But in duck stance position you just
pull back your inner ski and press down your inner toes and you get
bank easy. Your outer ski should be pushed forward, to paralell with
your inner ski binding, and by heel pressing you stabilize your ski!
With a turning radius of 15 to 17 m there is no need for hipp or waist
movement, instead point of weight should be straight down between your
skiis. This gives you a turning radius between GS and SG! 
With this technique you do carve in almost all conditions and when your skis carve they become much more stable!
The most obvious difference is how direct your skis becomes and
especially in the initiation of the turn, when going back to normal
stance it feels like your skiis are very sluggish!
We have also noticed that those who have problem knees do not get as sore as they use to be. Good for bad knees!"
well....