Just to add, I think this is the exact situation a heavy should be used for. Take the instigator, make the punk pay for even thinking about looking at your star player.
Screw the heavy on heavy code, if it's reactionary keeping scrubs in line, the code goes out the window in my opinion.
Pretty poor example, Rosehill is 6'3", 215 lbs, and his only job is to fight/enforce, he's more or less a heavyweight, just not a great one. I really don't see how Godard going after him is anything out of the ordinary, this isn't a heavyweight beating down on Matt Cooke or Raffi Torres.
Back when they were allowed to police the game themselves, they certainly didn't get away with it. Cooke would end up in a puddle of knuckles in the 80's. If you were that type of player in that era, you were a brave man, Cooke is not.
Those type of player were never as effective as they are now. It is the era of the pest/cheap-shot artist. They have free reign over the NHL and significant injuries to star players are at all-time high.
Ulf Samuelsson, Claude Lemieux, Dale Hunter, etc. were smaller players who never the less played like dirty rats during the 80s, and got away with it as much as the dirty rats of today get away with it. Your claim that enforcers eliminate Matt Cooke type players is clearly false. Somewhat of a deterrent, but if a guy can carve out a role as a "playing on and over the line" type in the league, to the point where it can means making millions in the NHL or jack squat in the AHL, a few extra punches to the face isn't going to stop him.