I'll have to try the boards and see what it does with them up. I've always just put them down and left them.
Don't bother. Leave the boards all the way down going upwind on the 18-2 always. These folks are talking about some high aspect ratio boards like the I20 and F18. Don't bother with your centerboards on the 18-2.
Just travel out about 4 inches and you should be good to go.
Mike Hill
www.stlouiscats.com