Sailing is slightly more complicated than that. Take a look at a polar diagram for a typical boat. They're fastest sailing at ~90 to ~120 to the wind, and gener

Sailing is slightly more complicated than that. Take a look at a polar diagram for a typical boat. They're fastest sailing at ~90 to ~120 to the wind, and generally you can't get closer to the wind than 30 degrees or so. Because of this the best velocity made good is often by alternating on two tacks rather than sailing directly toward your destination, even when sailing off the wind. There's a lot to consider when sailing. None of it is some sort of magic that can't be automated, but there is quite a bit more to it than how you describe it in your first paragraph.