Using the Alter Cup as your measuring stick for determining the effect of crew weight on performance may not be your best bet. While all crews are sailing the same boats, the boats are also set up identically. Adusting and tuning of the rig to maximize the boats performance for your weight and conditions is not permitted. ie....heavier crews were not permitted to power up their rigs in the light stuff and light crews were not allowed to depower their rigs in the heavier stuff.