Quite the contrary. The purpose of the jibing (tacking?) daggerboard is to allow the hull to travel closer to straight ahead, and not have to skew to its true path thru the water to match the boards angle (which it needs to generate lift). Therefore it is particularly applicable to long slender hulls.
The tests that are inconclusive that I know of are with monohulls, what with their bowl shaped hulls, dont really care near as much which way they are crabbing along. They are compromising for lean, lateral stability and low drag at low speed so their sterns sweep up, are wide and, well, bowl shaped. If you imagine a 20' cat hull's path when it is skewed three degrees to its direction through the water, the drag and vortex loss all along the underside length must be horendous.. In effect, imagine daggerboards are only allowing you to sail higher, but not really lowering losses over a boardless boat "pointed in the same direction"
I would further gues that tacking boards would, strangely enough, encourage a deeper slender hull aft, because the vortex loss would be zero. (The boarded hull would not be crabbing, and therefore not need to be less resistant to lateral movement).
Mechanically, I think there is a problem with the tacking boards design because the sideward pressure on the top of the trunk is oposite that at the bottom. i E IT NEEDS TO BE CUT the opposite way at the top (the board would be wedge shaped pointy side forward at the bottom of the daggerboard trunk, and wedge shaped pointy side aft at the top of the trunk. IMHO