ow! thanks Yes, it is nearly straight anyway. A wide board seems to lift the fin further out during a gybe, with my present style at least. So it seems to be doing something.. And it seemed better in rubbish wind and chaos water today. I read references to it "keeping the nose lower" during a gybe. whatever... A more pressing problem just now is finding a way to keep sand from jambing up Chinook mast bases. Frustration and joy in equal amounts...
Chameleon, thats me. Done by losing laptop and password, changing ISP and residence, and then making random efforts to get things straight again. Nothing really changes, except maybe replacing sailboards with kites in the Olympic games.
OK, so why is a curved fin "turney" ? I would have thought that extending a fin further behind the back foot would make it less 'turney". Could it be that getting more area for less depth helps by producing less interference with the gybe? In which case the curved fin is an anachronism and only retained due to surfing tradition..