The likes of England, Wales and France are happy to keep the number of re-sets high so they can paint a picture in the mind of the referee.
The more the scrums collapse, the more pressure is put on the referee to award penalties. That's why the Northern Hemisphere teams who back their scrum like to keep the ball in for longer. England are expert at manipulating scrum penalties, famously extracting six in one half against the All Blacks in 2010.
Statistics tell the story of the different mindsets best. In last year's Six Nations, for every 100 scrums, there were 49 collapses, 33 re-sets and 39 penalties or free kicks. Compare that with the 2011 Tri Nations where only 25 of every 100 scrums were re-set, or Super Rugby, where the figure is down to 20 per cent, and the nub of the problem becomes obvious.
In the Southern Hemisphere, the scrum is seen as a multi-purpose weapon; if the engagement is clean and accurate, the dominant side may indeed win a penalty if they exert enough force. A dominant scrum is a vehicle to create front-foot ball for the backs from which they can attack and score tries.
Constant collapse and re-sets are not the end goal, largely because they eat up enormous swathes of time. When Scotland played Ireland last year, there were 20 scrums producing eight collapses, seven re-sets and seven penalties and free kicks. Almost 20 minutes was given up to re-setting scrums.
That level of inactivity seems to be largely accepted up there as a valid part of the game. There is unquestionably skill involved in building that picture of dominance. Technically and physically, England and France are outstanding scrummaging sides and the process of grinding an opponent, of destroying their confidence by prolonged battle, is widely appreciated as a key element in marking rugby as a different football code to league.
The problem is that the constant collapsing and re-setting are integral parts of the plan to portray the other side being in real trouble.
So news that the forthcoming Pacific Rugby Cup will trial yet more scrummaging laws will surely be met with no real optimism or enthusiasm. The current 'crouch, set, engage' commands will remain but the twist is that the props will have to bind using their outside arms on the 'touch' call and maintain that through to the 'engage'.
Former All Black and chairman of the IRB's scrum steering group, Graham Mourie, said: "The scrum is a complex and dynamic area of the game and we are committed to working with our unions to facilitate the best possible platform to enhance player welfare, stability and the contest itself. It should be remembered that this trial in the IRB Pacific Rugby Cup is not a fait accompli but will be considered along with the current global trial of the crouch-touch-set engagement sequence."
Inevitably the latest trial will be adopted globally and inevitably, it will make little difference.