Well, yes, indeed, there is no better solution than to get help from high angels! (And in Colorado these days, many of our angels are higher than ever....)
I would not characterize his run as 50-50 i.e. 50% of turns were banked in...?
(Sorry, Pete--looks like your thread is going to turn into a discussion of edge angles (edge angels!) and how to--and how not to--get them.) Razie--I probably don't disagree with your observation, but I suggest that the mistake is to think of these things as "either-or." We incline in every turn we make--it is part of balancing. And we angulate--optionally and for purpose--to whatever degree we need, adjusting angulation with purpose throughout the turn. Angulation describes a spectrum, from "banking" (zero angulation) to extreme angulation. Inclination is a spectrum as well, but for any given moment in any given turn, there is only one degree of inclination (lean) that produces balance--it is not a choice.
There is a simple formula for how much our skis tip: tipping angle = inclination angle + angulation angle. Inclination (leaning) and angulation (bending) are separate, independent, and unrelated movements--we can do either, neither, or both, to any degree. As we incline ("lean") into a turn for balance, our skis tip with us, naturally. Incline 45 degrees with no other movement (in other words, "bank") and you have a 45 degree tipping angle (not necessarily edge angle--to be discussed in a moment). Tip your lower body (legs) in and your upper body toward the outside of the turn (angulate), and you can increase your edge angle without disrupting your balance (independent of how much you are, or are not, inclined). So, the angle of inclination, plus the angle developed by angulation, determines how much our skis are tipped.
Edge angle (on the snow) brings in a third variable: the angle of the slope. And even on a constant pitch, the slope angle varies throughout the turn, subtracting from the tipping angle at the top of the turn, adding to the tipping angle in the lower half of the turn, and zero at the fall line (straight downhill) part of the turn. So, edge angle = inclination + angulation + slope angle (which is negative in the top half of the turn).
(Image © Bob Barnes, all rights reserved.)
So what? At low speed--let's say, stopped--if you want high edge angle, you have to angulate, a lot, because inclination is zero. In a tight turn at high speed, on the other hand, balance will require a high degree of inclination, and you may not need to angulate at all to achieve the same tipping angle. (Sidebar note to the techies: I am ignoring, for the moment, "platform angle" or "critical edge angle," which requires at least a small degree of angulation--sometimes just a little ankle tension. Everyone else, forget I just wrote that! You can look these terms up in my Glossary.)
Add a steep slope to the high speed, and you may find that in the bottom half of the turn, the challenge is to reduce edge angle to prevent your skis from over-edging and "trying" to carve too tight a turn--possibly exceeding your strength, exceeding the skis' ability to hold, or exceeding the snow's ability to resist the forces you generate. In such situation, blindly following the advice to "level your shoulders, or angulate, in the bottom half of the turn" will be a (possibly big) mistake!
In any case, we must think of angulation as an "edge control movement"--not as a critical "standalone" movement in itself. It's like the steering wheel in your car--just because it's there, doesn't mean you have to turn it! (This is true of any skill in skiing including, of course, the "rotary" skill.) Need more edge angle? By all means, angulate! Edge angle sufficient? Hold the course--bank on!
So great transitions, in which the feet travel on their path toward the outside of the new turn while the body takes the straighter path down the hill toward the inside of the new turn, produce inclination--along with tipping angle--sometimes in the extreme. As the pressure/carving/shaping phase develops, if we need more edge angle, we often add angulation in order to further tighten the radius of the turn--if we need to tighten the turn, and if we, and the snow, can withstand the added forces it will generate.
Many turns follow just that sequence--incline into the turn in the transition, and then progressively add angulation (to some degree) as the turn progresses to tighten the radius and launch the skier into the next transition. Often too, as we decrease inclination at the end of the turn, we'll increase angulation, simply to maintain the edge angle and keep the skis carving a little longer. But it is a spectrum, not an "either/or," and it is purpose-driven, not "doctrine-driven." Ligety demonstrates that spectrum in the extreme in that run. Enjoy and wonder at his brilliance!
Angulation is a control movement. It is something we use, as needed--not something we "do."
Now back to you, Pete! In powder, in particular, the snow doesn't have much cohesiveness. It can't withstand extreme forces without pushing away. Two skis, with their added surface area, can support more pressure in powder than one. Furthermore, edge angle does not have the same effect in powder, as it is not the edge but the entire ski base that interacts with the snow. For these reasons, the need for angulation is often much less in powder. Banking is common--and often not an error--in powder.
And there you have it!