I know nothing about sailing, except that if the air flows along a curved path (sailing close-hauled), there will be a pressure gradient perpendicular to the flow direction, which together with the keel resisting the lateral forces, causes the boat to sail upwind. But there is theory and practice; in a once and never again attempt I drifted to the other side of a small lake and had to walk back.
Though it helps to know something of your subject (and the rules of a regatta) before taking up a photographic assignment, it can be fun to get out of your comfort zone. There is no such concept as slowing down, to which I normally adhere to, when you stand on an unstable zodiac, the subjects are moving, and you must compose and focus hoping not to be washed overboard with the equipment around your neck.