FWIW, I do most of my skiing these days at Whitewater, British Columbia. They have a little powder now and then.
I first learned how to ski powder at Berthoud Pass, Colorado. They have a little powder now and then, too. It's generally lower moisture powder than what we get at Whitewater.
I have re-learned how to ski powder several times since Berthoud Pass, often in clinics given by certified trainer types. I have experience with a variety of different consistencies of "powder," ranging from really light to really wet.
I have used fat skis many times, but I don't actually own a pair at the moment. I do most of my powder skiing an a midfat with a 78mm waist. Hey, I get more face shots than the fat ski crowd!
So....the initial description does indeed sound to me like a fairly old school, high energy way of skiing powder, and it's the way I was initially taught. It's a fairly complex movement pattern, it encourages exaggerated, inefficient movements, it doesn't take much advantage of the characteristics of modern skis, and it's not well suited to novices, IMHO. It also encourages an attempt to perform an abrupt, exaggerated rotary motion while the skis are relatively unweighted. The necessity for it is driven by the belief (and initial feeling) that the skis cannot be guided into a turn while completely weighted and submerged in powder.
This is not true. Most powder is compliant enough to allow the novice powder skier to tip and guide the skis into a turn of surprisingly reasonable radius at low speeds even while the skis are completely buried. Retraction adds a great deal to one's powder capabilities, and can come fairly quickly once a skier gains a little confidence and learns that the skis will actually turn in this new medium, but it's not initially necessary. Skiing with just tipping and guiding simplifies the learning process and teaches the skier patience, which really is necessary in powder. While some guiding (I hesitate to use the word "steering" - we're not attempting to pivot here) is quite possible, Z-type turns are very difficult and do indeed require some kind of dramatic unweighting to accomplish.
Speed is another thing that, like retraction unweighting, is very helpful in powder, not to mention a major addition to the fun factor. But it is possible to do one's first powder turns without it. Initially, KISS. Balance, tip the skis, guide the skis. Have patience, butterfly. They'll turn.
Until recently I did all my powder skiing with small baskets on my poles. Correct pole usage is important, but a strong blocking pole plant to help unweight may be impossible, even with big baskets. The snow itself, combined with a little speed and the vague shapes one finds underneath are much more useful than attempting to push on one's poles. I finally got bigger baskets because the traverses into the sidecountry at Whitewater were awful with small baskets.
Regarding point number 8, when my skis are pointed straight down the fall line, they are generally tipped and turning, but they have not "risen." They may be at or near their deepest at this point and I'm probably fairly close to maximum extension because my skis are well out to the side. I start retracting after
the skis have already turned out of the fall-line a bit.
Point 7 implies a pivot turn entry. Now, I freely admit to doing plenty of retraction pivot entries to turns, especially when trees are involved, but if one is skiing in the open with a little room, a pivot entry is not required. In fact, in some conditions, a pivot entry is extremely difficult. Tip them over down the hill. As the skier's weight settles on the skis, they will decamber even more than they would on hard snow and the tipped ski will enter the next turn quite nicely without much effort from the skier.
That's my take, and I'm sticking to it at least until, oh, 20 minutes from now when someone who knows more than I do (um, that would probably be almost everyone
) chimes in and tells me I'm all wet.