JASP's suggestion to loosen up the hip socket is not bad, I don't have a problem with it, which may shock him to hear, but its true. This skier has a dead lower half and hyper active upper half. They need to activate the lower half and quiet down the upper half. Lots of pivot slips would not be a terrible thing.
There is a big difference between pivoting the skis and relying on that to initiate a turn...vs simply moblizing the hip socket. Even highly carved turns, especially SRT, need the femur to twist in the hip socket a certain way. Pivot slips can help to develop that.
I don't particularly think this skier in question has un mobilized hip sockets, but this skier is definitely not initiating turns with his feet AT ALL. its all happening from the gross upper body movements that JASP and LF have described well. The feet are being pulled along for the ride rather then being the hands controlling the steering wheel.
He needs to learn to start turns from the feet and keep the upper half quiet.
One way of doing that...the way heavily endorsed by PSIA with a capital R, is using rotary to initiate the ski pivoting and creating early steering angle. That's not the only way, and we can get into another pivoting debate if we want, but seems like that should be on a different thread, we've battled that out countless times. Bottom line, is that this skier needs to use the lower half to start the turns. He can do it with heavy twisting as JASP is endorsing and it would in fact be an improvement. My own personal bias, is that the skier will be better served to learn to tip the skis first and get the skis to perform, also with emphasis on keeping the upper body quiet.
Somewhere between zero pivoting and capital R turn entries is a happy medium place where the skis are tipped, are performing, are steering, whether self steered or twisted-steered...and the upper half remains quiet. There are definitely different approaches to get there. JASP's PSIA approach will have heavy emphasis on the rotary aspect and will at least get this skier out of the mode of hucking their upper body around to pull the skis into turns.
My own advice is the same as before, and probably resonates better with you Razie, which is to tip the skis, get them to perform and make turns, also while learning to keep the upper body quiet, relying on footwork to get the skis to turn. But even coming from that school of thought, I am not opposed to pivot slip work if a skier needs some mobility in the hip socket. This skier has been twisting his upper half the wrong way for a long time, so pivot slips would probably become a drill at some point, even coming from me. Also counter-action drills.
Where rotary goes too far is when it becomes the bread and butter foundational skill for making the skis turn. When the skis are actually pivoted on the snow, sidecut performance is severely compromised. Learning skiers in that mode will thus not be even feeling or experiencing what their sidecuts are capable of, nor developing requisite skills to do so. So too much rotary emphasis can really be a problem, no argument there Razie! I just think this particular skier is so far the other extreme with his upper body stuff, anything at all to activate the lower half at this point will be a good thing. If he gets too much pivoting into his skiing, he will have to come back and fix it later, that's true. Or he can just ski like numerous division examiners, trainers and TD's I've seen skiing around with too much rotary and thinking they are good...eh...whatever works for him. That rotarized approach can be taken quite a ways. But ultimately right now, he has a lot of stuff severely backwards in terms of dead lower half and hyper upper half, so as far as I'm concerned, he has a lot of changes to make and a long journey in front of him...and any of that kind of advise that involves activating the lower half is going to help.