Dick, it would seem to me that a thicker airfoil would mean that there is a bigger curve in the foil and hence more room behind it that would have low pressure and that would in turn create more lift. (not sure I explained that well) Like I said I am no pro in airfoil design but it would seem to be that would be the case. Also, I cant remember who told me the slower dive thing but I am almost positive I read it on a post. But it would have to dive somewhat slower if for nothing more than the thicker airfoil creates more drag.