The lateral pressure on the board holds it sideways. With the boat on the beach you can grab the board and move it in the case. Its a very tiny amount and would only change the angle of attack by 1 or 2 degrees maybe less. But its enough to make a difference. In flat water you can feel the board flop over as the boat accelerates from a stop or out of a tack. I feel that the boat really tends to travel towards whatever you are pointing it at with no or very little leeway. Thats what is supposed to do and i think it works.