Thanks for the vote, Luiz. I actually pull my boards all the way up when sailing downwind, so that's not an issue.
I think the difference is only the following - if the pivotpoint is at the rear, as mine is, the angle is less than if you did it where the pivot angle was closer to centerline of the board (Phils foil diagram). I suppose I could grind/fill my board somewhat to change the pivot location and increase the angle when boards are down.
But I'll procrastinate some more before I do that.