true you can't teach natural born pure athelticism but this applies to all positions. but there are two things you cannot teach speed & size, although you can enhance through training, nutrition etc....its much more rare to find a stud NT than a stud linebacker when you have a multitude to choose from. there is not a blue chip top 10 DT/NT in the whole draft for the second straight year, only one (NGATA) in College football
