|Well trimmed sails won't flap|
When you are at the wheel, there's a compass right in front of you. Look down a bit, and if you are one of those ppl with huge boobs, you're in trouble. Me, I can see the compass just fine, and yes it does rotate... or rather the compass stays still while the boat rotates.
|Windex tells you apparent wind direction|
Up the mast is a pretty little helper-thingie. It is the well known windex that more and more boat builders now seem to include, and that i soooo nice. No more texthuds needed. Just look up and you know the wind. Just like a real boat.
|Heeling tells you windspeed|
But it doesn't tell the windspeed, and there's no meter saying how strong the wind is. True. No need for a windspeed readout. That you must figure out yourself from the heel. Once the sails are trimmed, she will heel over according to windspeed. The boatspeed will - ofcourse - also be affected by this.
That's really all there is to it. It helps a lot if you have a basic understanding of windangle versus sail angle. Downwind the wind hits the sails with a 90 degree angle and simply pushes the boat. Upwind it is a different story. Upwind the sails are almost aligned with the wind creating low pressure on the back of the sail essentially pulling the boat forwards.