working the boom vang
I understand that you use the boom vang in winds about 13-15 knots and above to flatten the sail to lower the drag by decreasing the depth of the sail. But I read that in winds of 17-18 and beyond that some have a differing approach: they recommend loosening the vang in order to loosen the leech, allowing it to twist and spill air at the top. Doing so, they say, takes the pressure off the top of the sail, decreasing the heeling moment, thereby making it sail flatter. This loss of power doesn't affect boat speed they say because the winds are already high and the boat already maxed out in speed, and the absolute goal is keeping it flat. Thus spill the air. Any thoughts out there re this?