If they got SF training as they should I'd do the PF. What I am saying is that 6'7 being the middle point thats farther to optimize training in either direction that 6'10 is 3 inches from it and 6'1 is 6 inches from it. So training the 6'1 at guard skills would result in faster pops than the 6'10 in center skills, but then again the 6'10 could be a good all around player. But as you said it was valid point anyways with the grades so you can't really go wrong with either.