How did you feel about the necessity of punishment as a training tool?

To use an old Southern expression, "there's no education in the second kick of a mule." Corporal punishment works in education. There's an old R. Lee Ermey interview where he admits that he could have talked to a recruit that was causing issues, but that doing so would have taken time away from his other recruits, thereby hurting their Vietnam survival chances... so he'd just hit them and move on.