The windurfers have lead the way here. They went to the extreme a while a go and most of the latest shapes have gone back to just a mild undercut in the leach.

For us currently, I was informed by some of the sail measurers, that there is a penalty in measured sail area vs. actual when measuring a sail with a reverse leach.

Windurfers for all intensive purposes do not adjust downhaul, outhaul, or "sheet" tension. While I am sure it is very debatable, I was told that when this style top was experiment with on the A class sails, there was signifcant added drag and they were not nearly as fast. An interesting note would be also to see that even with 0 or positive roach the trend to have realy large heads on cats has moderated.

M