really? I don't think there would be significantly more drag as the same sideforce would be needed but you could generate this without the angle of attack produced by the leeway, you may even have less drag since the hulls would track straight throught the water
I know C-Class cats make use of this
Think of airplane wings - aysemetric wings are used on low speed aircraft. High performance wings (less drag) are fully symmetrical. On the scale of things between an airplane wing and our foils in the water at the speeds we sail, the relationship is very similar (Reynolds numbers). Generating the same lift, a symmetrical foil will provide less drag through the water. I don't know what the C-class guys were doing...but more can be done with the angle of the board to present lift to windward and/or lifting force (and, you won't have to gybe a symmetrical foil like you would an asymmetrical foil).
