George: the M15 isn't underpowered. a larger main can have advantage in light wind, but you need to reef earlier. Dan's M15 is a 'one-off' so he can better speak to the sail area differences. you don't want to go 'to big' or you have a sail with a center of effort in the incorrect location. another consideration is a larger genoa for light wind. this would involve, at minimum, adding a block on the toe rail for the changed sheeting angle (a block on a sliding track would be better). i wonder if your headsail is the same size as a stock M15? your standing rig is different so it may be smaller (a guess, i have no idea). :: Dave Scobie -------------------------------------------- On Thu, 10/24/13, George Iemmolo <griemmolo2@gmail.com> wrote: Wrinkle Boat Mates Am in the process of buying used standard sail from Daniel (Have you heard anything from Judy B/Hyde yet about your new sails?) Was wondering What the difference in the Main SA is between a standard Main and a Fatheaded Main. As I sail on a inland lake in NWI I have found that I am in light air most of the season. Much different than Lake Michigan my previous sailing venue with my Pearson 23.