Hi Jake,
With the forward located CB and spin up everything is in balance and no lee helm. Now take the spinnaker down. The CB is still forward. Therefore the CB will be exposed to and carry less of the side load from the sail because the sail CE is now further behind it. What other foil can carry side load? The rudder! Now the rudder will carry its norman side load plus the additional side that the CB is not carrying because of its forward location. The next step is to match the CB and rudder areas to the loads they are carrying. Therefore relative to their base sizes, the CB can be made smaller and the rudder should be made larger. This results in the same effective CLR location as the base boat configuration but with the forward CB location, the CE cannot get in front of it, spin up, to cause lee helm.
Jake, the forward daggerboard placement does not help prevent the rudder from stalling. The increased rudder area helps prevent the rudder from stalling. The trem is called rudder loading and its units are force per unit area or for example pounds per square foot.
Bill