How you should slow build a player depends on position and how you want to build him. For some positions, the way to slow build is to assign all your sps in one stat while training another. There is no reason to horde.
However with other positions, especially if you are building a balanced player, then it can be good to assign enough sp to stamina to maximize your players PT in d-league and horde the rest while you train on several different attributes.
However with other positions, especially if you are building a balanced player, then it can be good to assign enough sp to stamina to maximize your players PT in d-league and horde the rest while you train on several different attributes.