On your webpage you wrote :

"I discarded the main sheet and played with the traveler sheet, which I occasionally dumped when we were overpowered. ... In 25 knots I found us having to almost run to keep control, which caused us to nose dive several times."

How strange it may seem but when you are running almost straight downwind and you are likely to dive; don't sheet out your maintraveller. Chances are you are to late to prevent decelleration and because you go slower the apparent wind is likely to turn from perpendicular to the centreline to behind your boat. By sheeting out your traveller you rather increase the projected surface and make sure you go into a proper gibe. Rather let the main traveller and the main sheet be.

Another trick used on sloops in heavy winds is to not set the jib to tight. Sheet the jib just tight enough so that it doesn't flap; it doesn't have to have a nice shape. Often with a spi the jib can be set rather tight and when you suddenly drop the spi the jib power up quickly and give a push to your bows. Or at least that is what the local F18 champion here advices to do.

Here apic of two Mosquito's with spis in South Africa



Wouter