Many racing mono's have waterballast (Volvo ocean, Classe Mini (the open fleet), large cats and tri like Orange). Many competition landyachters put (bags of) sand in their **** during days with strong windsI guess the designers of all these championship craft are just misguided.
Wouter
The designers of the above craft were not misguided, they just had an understanding of how sail boats work... unlike some on this forum...
I will attempt to explain but dont freak out if you get lost along the way, its complex and involves thought <img src="http://www.catsailor.com/forums/images/graemlins/smile.gif" alt="" />
on a Displacement boat (not a performance catamaran/multihull as the displacement rules dont fully apply to such a craft) once you reach hull speed then weight is good. it helps stabilise the boat and allows you to carry more power. it also helps with keeping speed during direction changes such as tacking. more momentum into a tack equals more speed on the way out.
in the AC boats they have huge water bladders to fill with ater once the wind speed is such that the boat will be travelling at hull speed upwind. On the Farr 40's we put as much water as allowed in the bilge if the wind is strong enoug for us to reach our max VMG upwind.