New Zealand Rugby is making three changes to age grade rugby this season in the interests of safety.
All tackles have to be belly or below, there will be no jumping for high balls and players must use a split-stance when guarding the ruck to lower the chances of necks and spines being exposed to when opponents clear players out.
Former All Blacks coach John Hart told Mike Hosking it's understandable.
"Numbers are down and the concussion area is a particular area of concern.
"I think these sort of moves are very good at trying to eliminate some of the high level head clashes that you can get."
He says that the neck and spines rule is the toughest on referees.
"They've got enough issues at the moment, so that's a bit more difficult, but at least it's a principle of trying to get a better balance of players over the ball rather than putting them in a position where they can be hit and injured."