Well if you put the current and potential ability as 200 and you make the player play in all positions then yes you can get 20 for all stats, but if he is a striker with 20 tackling and etc, the computer will sort the thing out, and the stats will be decreased, i played around in the editor in 09 but im not sure about 10, i couldnt get 20 but i got ibrahimovic's finishing,dribbling and acceleration to 19.