We may be using terms slightly differently, Rob. What my friend means by "wearing" his kayak may be different than what you describe. I believe you and I are on the same page, but let me clarify to make sure. My friend contends that he controls the movement of his river kayak and maintains his balance by opposing the action of waves, current and wind with his knees. This is where my friend believes a ski would benefit from knee straps, or some solid protrusions of the boat akin to knee braces. He believes he feels unstable and tips in a surf ski because he does not have knee braces or straps to hold himself in and control the side-to-side pitches of the ski, as he does in his river kayak. I don't think you are saying that you control your ski that way, but perhaps you are (????)
I certainly feel as if I am wedged into my ski between the feet and hips, and in that sense "wearing" the boat. I use those contact points in concert with the paddle and torso rotation to move the boat forward, as you describe....the standard technique...and in that way, I am very much "one" with the boat, at least on a good day. So while I power the ski forward with my torso and hip rotation in the plane of the long axis of the boat, I try to be totally relaxed and let my hips "float" with the boat as various forces cause it to roll a bit to one side or the other. In other words, I am quite actively engaged with the ski in the long axis, but passive in the short axis. Of course, occasionally, I have to use a brace stroke, but the more relaxed I am and passively centered in the boat, the less I have to rely on active corrections, like a brace stroke. It seems to me that a ski is unlikely to tip without a paddler in it...it is usually misdirected weight shifts of the paddler that cause a tip, rather than not enough correction. With this technique of balancing on the ski, knee straps would not help...in fact, they would hinder.
Am I understanding you, or do I have it wrong? Should I be trying to actively correct the boat for side-to-side movements as waves, wind, and current affect it? If so, then my friend is correct that I would have more control with knee straps. Or is there is a difference in the way one keeps a ski upright, as I describe...more of a relaxed balancing than active correction?
Sorry for the anal-retentiveness of my questions, but I'm trying to learn long-distance...no fellow surf skiers in my immediate area to learn from. I hope some other beginners are deriving some benefit from the conversation.