As I've said, I only want to see him squirm. What you do with him is your business; as long as somebody's holding his leash, I'll be happy.
[she's not explaining this well because Dersite Problems, but what she basically means is giving PM any sort of upper hand over Jack is enough for her. all she wants is to watch him (biologically impossibly) sweat.]
If you have a firm grasp on his leash, he'll be less likely to snap at you or anyone else. If he knows you can best him at any time, he'll be more cautious. He'll take his time, giving you more of it in turn.