Development of Proa Squared along with boards tested.
http://www.youtube.com/watch?v=DG1LuSq_CLg
In the video the proa squared free sailing version worked fine with the single 4 1/2 sq inch with about 3- 3 1/2 sqinches of board submerged. It actually tending to bear off the wind more than I expected with this single board down. So the bigger boards where not tested in single board down configuration. I proceeded in using the two of the smallest boards for two board down sailing. What I experienced was heavy weather helm no matter how hard over boards were held over they were over powered by the sail the model was uncontrollable shunting, sailing in a straight line etc...Lots of finesse required and even then very frustrating. So I jumped up to the second 1 1/4''x 5'' larger retangular board wha la great success balanced sailing and shunting just a touch of weather helm coming out of a shunt . On on the hard though hands free sailing straight.
With this design of craft shunting happens so fast the advantage of leaving both boards down is quit significant maintaining control and predictability allows me to sail faster not the other way around fight helm to maintain control.
enjoy
Todd