Given his propensity for domestic violence he should get one. Its an honest challenge to him that he will never do because he would look utterly shit.
There was a kid in my neighborhood when I was young who was prone to doing crazy and often violent stuff and his parents put up a heavy bag for him to wail on to vent his aggression.
It didn't work.
One time he got mad and threw a hatchet at another kid. Fortunately it hit flat side in the other kid's back.
Later in his teens he sexually attacked a local girl.
As an adult he became a youth counselor. Go figure.
