I don't disagree with your post but I would like to discuss more on what you say. I would question the possibility that couldn't it really be more of a technique learning vs the ski actually being too far above his ability? I know hes not coming from old school straight skis but perhaps those 2000ish K2's simply did allow him to ski much more of his older style of straight ski skiing. When I came off straights (embarrassed to say....lol) just last year I had similar problems. I just needed to understand the newer technique and sort of re-learn some things a bit differently even though I was an advanced skier prior. But its not like it required me buying an intermediate ski and spending very long time gradually lerning to ski again to the same relative level. . The Bizzard xpower810ti is not an intermediate nor real forgiving ski. Point is it just took a newer understanding and a few ski days to learn how to drive them and while I still can improve some, I do ski them very well and enjoy the heck out of them. So is he simply skiing old school but at a high enough level where all he has to do is get some technical help/pointers and a little practice? or is his level not only old school but also intermediate level? The difference between the 2 answers may be what dictates between just needing to learn a little differently vs indeed being in a ski not forgiving enough for his ability.
You make all valid points. Your view is also 100% viable. No real wrong view with any of the options.
We're all just shooting the sh&%t over some Koolaid...
The only real answer is what the OP decides to do... Cantunamunch, roundaboutly notes there may be more 'fun' alternatives to a 78 waist, technique demanding ski, when it comes to a daily driver.
OP needs to decide how much dedication he's willing to apply to really enjoy skiing the Stocklis, what level of dedication and demand is really an unknown.
If he's enjoying the challenge, then 'rock on'. If he want an easier and possibly less demanding transition, there are those other options. How many days does he ski? Where?, What physical condition is he in? All these impact on all of this and again only he knows...
Skiing, like so many other wonderful things, is all about the journey, mostly not the destination - 4 PM at the car, agonizing while taking the boots off, ain't the gates of heaven.
Heaven can happen any/every second between 8:30 and 4 (or WHENEVER you decide to let it all in)