The advantage of having the daggerboard so far forward is that the center of effort from the sail plan "with a full size spinnaker up" will not migrate to infront of the daggerboard and cause leehelm which is additional rudder drag and therefore slows the boat down.
I see a couple of additional advantages:
- The shorter daggerboard reduces the maximum draft, which is good for sailing in shallow waters.
-Moving the daggerboard forward allows a less disturbed flow of water to reach the rudders, increasing their efficiency.
The Catri is another boat which uses the same concept. Interestingly, it was conceived using a totally different engineering background - former Soviet Union technology.
Cheers,
