Interesting stuff to consider. I guess there are a lot of factors that come into play for each of us.
I'll avoid binding Delta for now.....
Yes, our son is 30, very strong, very fit, and(knock on wood) has never had lower body injury. He's the type of skier who turns every head on the hill. And he generates a lot of edge angle even on his widest skis. I hope that he's not doing a lot of damage. He's very compact in his skiing stance. He'd built for the sport. He will pick his skis for the day. Most of his days are such that the Enforcer works, I guess. If he were back East, they'd get less use.
I'm 62, 5' 10" and about 200 lbs., the lightest I've been since I was 16. I've been skiing since I could walk. Ski about 80 days a season these days. I prefer to ski the right ski for the surface, too. If it's rock hard, it's a GS Cheater. If it's merely a bit firm, maybe well groomed, it's a toss up. Might ski my 80mm ski. If it's mixed up and soft, probably my 98mm Bonafides {I'm a fan of the ski, unlike many}. A lot of snow, Bodacious. I ski each of these in the longest length made, other than the cheaters
which are 180's. I'm pretty "current" with my skiing, not so much old school.
I don't have {again, knock on wood} any knee pain, no hip pain. However, if I were skiing a 98mm wide ski on real hard snow, I am sure I would. That's not why I choose a narrower ski, but it seems obvious. I don't see many guys my age "sparkin' arcs" on wide skis and real hard snow.
But I do find myself skiing deep snow on my 196cm Bodacious, and sneaking back to the lifts on groomers, and they work. If I tried to get them way up on edge in those conditions for a few hours, it would be tedious, ugly, and likely painful. Not the right tool at all.
I have skied an 84mm Firearrow EDT for long days on end on hard snow. That's a hard snow "weapon". No knee issues for me. It's got to be more than width, I think.
I'm not a medical professional, no engineer, etc. I would think that somebody like Brian might have some thoughts and insight.
In general, I would guess that many folks might have been better served with a narrower ski, depending on location, in recent years. Back to people buying a ski based both on how they would like to ski, and what they would hope to ski on or in rather than reality. I see very average skiers on shortish 98mm Mantra's as their Eastern one ski quiver, and that looks and seems wrong most days. Rarely do they seem like they are being skied as designed though. Big difference between a 98mm ski and something around 80mm.
Not to sound like a jerk, but the more skilled the skier, the more fit, the more likely they can match the right ski to the surface and have one in the closet that works! The
Just my hunches.
Binding Delta.....hmm. I'll stay tuned.