Hi GP
I politely disagree.
Of course the CoG is high above the wing yes, and you also got the vector component from the kite (lines and direction).
But IMO we can quite easily find an angle where the hydrofoil feels very neutral
As the kite is always in the same angle typically, both in height and L/D (forward vector).
Yes, accelerating and decelerating will influence, but this is natural and easy to compensate in the small amount of time when this happens.
The best example I can give is when going far downwind, and looping the kite forward and backward all the time.
Here you get a huge amount of accelerations in a short time, both ways.
And this is quite easy to compensate so you ride pretty level - does not take long till one masters this.
An extreme example though, as when riding with the kite parked or small sinus'es - the acceleration we get is almost nothing.
If your foil tend to seek "up" when you go faster - have you tried shimming the stabilizer a bit up, and see how it actually works when riding at different speeds ?
Mine is neutral - so I dont need to put more weight on my front nor my rear foot, when going faster or slower
And if we look away from the acceleration issues (meaning force vector is changed a lot high above the wing) , I can not see ANY theoretical reason why it would not work exactly as gliders - they dont search up nor down, no matter what speed you experience, when trimmed correctly for speed flight.
It also coincide with the experiences I have out there, that I can ride at different speeds without having to move my feet positions, nor change weight distribution
But of course, very different kite "positions" can slightly change the trim, yes.
PF