On the Ropes
For most applications the ultimate goal is to have running rigging that does not stretch at all. But why? Whether racing or cruising, the fundamentals are the same – any stretch in a halyard or other rope changes the sail shape.
Therefore in gusts the sail develops a fuller shape, with draft – the position of maximum depth – moving aft. This powers up the sail, increasing heel, and loads up the rudder, increasing weather helm. This, in turn, makes the boat more uncomfortable and more difficult to control in gusty conditions. It will also be a lot slower.
By contrast, if the sail shape remains constant in a gust, all the extra power goes into making the boat go faster. It also makes it possible for the helm to feather up two or three degrees into the wind to reduce power – but it’s next to impossible to do that smoothly if the boat
