Sorry for being quiet for a week. I was launching my boat after more than six years of work. It floats. It motored well. The sails were hoisted, checked and sent for small adjustments. Sailing trials soon.

The wind energy X height graph is very instructive. It evidences that air-water friction reduces wind speed at the sea level. I guess we all knew that intuitively but never rationalized that perception.

In view of that, it seems reasonable to cap both the mast length and luff length. I suggest we leave about 800 mm difference (slightly under 2'8") between them. Each designer can decide how much the increase of energy availability justifies increasing heeling moment and weigth within those 800mm.

Agreed?