Not sure if this has been covered before however.....
To achieve "maximum" speed for your sail size are you better to be picking a sail that you are consistantly overpowered with or selecting a sail that does not spill out the wind all the time?
Hardie is right about control and Bender is right about the outhaul giving you control. A smaller sail can be more efficient if you are a lightweight. I have suffered trying to hang on to a big sail when those on a smaller sail are going quicker. It also depends on type of sail. Bagging out a cammed sail is ok but does not work for wave sails. Had some great runs on wave sails but as you go broad they do not hold the profile and lose the power.
