Windgenuity said..The Handle thing is an interesting view point. I really like having multiple options for my grip. After quite a few goes now on the wing and getting consistent glides on the foil and riding from super light to heavy winds, I use different handles for the following,
Front hand/arm,
Forward handle - Good for baring away and floating the wing more / running a more over head angle with ease.
Next handle back - Most all-round handle. This balances well with the back hand on the 3rd last handle. It does make the rear hand a little more positive (more powerful back hand feel) and generally where I like to be when nicely powered and reaching.
3rd Handle back - Power position. This tends to put the wing into a more vertical plane. This is good for punching upwind and staying more sheeted on as the straight front arm takes a lot of the load and the back hand just trims.
Back Hand/Arm,
3rd handle from the back - I use this one 90% of the time. It seems to be a good sheeting angle with and compliments the above positions well.
2nd handle from the back - This is only used sometimes, mainly if it is super gusty, I combine this one with the 2nd from he front and have a wide grip. It makes controlling the wing easier while getting flogged by a gnarly gust.
4th handle from the back - I use this sometime s along with the 2nd from the front or absolute front handle when going down wind or when super powered up across or off the wind.
5th Handle forward. I use this for sailing with one arm. The wing balances here relatively well in light air. Helps to get the wing out and clear easily.
So all up, I am using a lot of the options in a variety of different conditions. I can imagine on a long DW'er having the option to get the balance point close to if not perfect a really big thing, as when it neutral it's weightless. and going 10+km would be a dream.
I think some of the battened (non Luff-Strut) wings out there will have trouble covering the same wind range and trim range as the Wing-Surfer. But I am bias

More coming,
regards,
JB