The subject is can you tighten a turn with the edges engaged. I think we all agree that at the apex and under maximum load steering is not going to have much effect. So the original description is a bit questionable if we assume the majority opinion is steering at the apex adds little. Not sure we can state that emphatically though. Tightening the radius of a turn was covered in Larsson and Majors landmark book, World Cup Ski Technique. They used a photo montage of Klaus Heideggar of Austria in the 1978 Kitzbuhel slalom and they broke down the turn he made into five frames (pgs 40-43). The commentary corresponding to that montage exposes the inaccuracy of the theory that minimizes the effects of ILS and U/L separation through the apex of a slalom turn. Notice the progressive medial rotation of the left leg (stance leg) through the apex where maximum pressure and edge purchase occur. By the final frame a redirect of about 90 degrees has occurred, Consider the fact that at frame four he is in the air, making it impossible for edge and pressure to be how he redirects the skis. Yet in frame five the commentary starts with the following " As he steers the skis around the pole, Heidegger's chest faces the outside of the turn. Again he weights only his outside ski which flexes under the pressure."
In her 2000 book Ski Faster Lisa Densmore talks about how carved turns changed due to the advent of shaped skis. Leg extension that occurred at transition back in 79, now occurs at the apex and the turns themselves resemble what we once called retraction turns. She goes on to talk about touch and feel for the snow. Too much pressure too early screws up the line and creates a need for a line correction many call a double turn. Beginning the turn at the rise line and being patient until you arrive there is one suggestion she offers to correct that issue. She also talks about how winners think about minimum edge angles instead of maximum edge angles. A concept many here dismiss in their quest to always develop higher than necessary edge angles. It's fun to feel those high edge angles but often that fun leads to habitual over-edging. A habit Squatty Schuller helped me break about ten years ago when I was practicing slalom turns. Years later Barnes and Sear helped me further refine that in my reaching slalom turns where flattening the skis became just as strong a focus as reaching whatever edge angle I need at the apex. Which I immediately thought about when I read the OP's description and the suggestion that ninety degree edge angles were something they were working on. Extending out lateral RoM as far as possible is something we all experiment with but once we can do that ultra high edge angles turns, the question of where that would be appropriate comes up. Booting out is a very likely outcome as you experiment with that ultra high edge stuff. So be careful.
Fast forward to today and while establishing an edge in GS and the speed events is apparent, pressure before the rise line is not there unless the turn features an opening radius "comma" shaped turn. In slalom a strong redirect is very much present in all the races I recently watched. As is the ILS and U/L separation described by Larsson and Majors decades ago. Like Lisa suggested most of the upward redirection of the core is gone and lateral leg extension is present. The skiing resembles Barnes' trampoline turn video and their feet swoop around just like his infinity graphic suggests. Add some of the reverse pedaling action because of the leg flexing that occurs and the model is fairly complete.
So while some may write dissenting opinions and suggest I am suggesting radical stuff, a Flat Earth, 2+2=5, naked emperors, or whatever silliness they choose, the simple truth here is four decades of writing by some of the sports best are the basis of what I have shared. In the end believing otherwise doesn't invalidate what I have shared and I don't expect them to change their hard line insistence that their dogma is gospel. I do hope the average reader sees the blind spots in their theoretical philosophies. As I stated previously, tip pressure can be produces a variety of different ways and through active experimentation a skier can experiment with all the possible ways to create and manage tip pressure. Enjoy the exploration...
Edited by justanotherskipro - 3/29/16 at 4:22pm