Dear Jules,
I am not an expert, but over the past year I have finally come to realize that the powering down the jib sail in high winds is the trick. It sounds from your post that you powered down the main but not the jib. I have learned that the crew has an important job controlling the jib sheet. I used to think that I would tell the crew where to cleat the jib and that was it. Now, I know that I was wrong. They have half the power in their hands, and they need to adjust according to conditions.
Greg
H14, H16