Just to correct a point from David W - I did not take out the WHOLE floor of Crazy Diamond, only the section from the front tank back to where the helm's feet usually are. The rear floor was left intact as a bouyancy tank and the section each side of the centreboard case was also left effectively forming a further bouyancy each side of the case. The central tunnel was also left in the boat from the back of the case to the transom, so that when you capsized only holf the boat filled up and then, because there was so much bouyancy, most of the water went out the back leaving only the footwell on one side with water in it (to be dealt with by self bailers or bucket! - effectively semi-self draining. Only problem is when launching in that water does come into the boat from the transom, but it far easier to right the boat at a capsize as it does not float too high in the water. Probably a fair compromise but it is also easier to get under the boom and more comfortable for the crew especially with a thwart to sit on. For the technical stuff you would need to talk to Mike Cooke who did the work.