Been following this thread since its inception with some amusement and incredulity. Clearly, the bar fight over how a sail provides thrust, (that is what makes one move, is it not) will not be settled here. Crawled out of my office the other day after flying it back from SNA to Dallas at 45,000 feet, and not once did the thought of Mssrs. Bernoulli or Newton come to mind. I think Catalanc asked how to set the jib fairleads, not the intro to aerodynamics 101. As several have mentioned, sailing on jib alone is a very practical and low work load form of no-compete sailing and I do it regularly on my C320. Windy day, old guy, why keep score? It promotes cheating! Buy Dons book, learn the function and effect of "all" the sail controls. Get a hand held GPS, go sail, move stuff around and see what happens. Empirical study has debunked more than one "theory". And go sail with some of the guys that finish up front in the beer can races. They may not know why they win, but they sure know how. And the next thing you know you'll want a bigger boat.