"First they go to one extreme, and then the other."
Since you did not specify which "extremes" you were talking about and the subject was Corporal Punishment, I inferred that it was one of the "extremes". Heading toward the other end of the scale, I concluded that you were implying a lack of discipline as the other extreme.
Please define the extremes to to which you referred.
No, corporal punishment isn’t an extreme by itself. Abuse in the guise of such punishment certainly is, though.