The financial costs of the status quo have been plainly stated. Eden Park, which had a $250 million upgrading for the Rugby World Cup, has to service a $55 million debt. Mt Smart Stadium needs a $60 million upgrading of its facilities and increasing its capacity from 22,000 seats to the 30,000 that league would like.
But the cultural costs of the plan are no less real. Sports express themselves in venues that become closely associated with them alone. Eden Park is known to rugby fans everywhere in the world as New Zealand's premier rugby ground. The idea of mixing its regular use will be as unwelcome to rugby's fraternity as it is to league's.
The Warriors' foremost fan, Sir Peter Leitch, spoke for both codes with his response to the plan. "When you think of Eden Park you think rugby union," he said, "Think Mt Smart and you think rugby league. That's the reality." A Warriors match at Mt Smart has an atmosphere the game has not found at Eden Park.
Indeed, it takes a rare rugby event on the scale of last year's World Cup to bring Eden Park to life. Auckland Rugby and its Super 15 franchise should make more use of the smaller North Harbour and Waitakere stadiums for crowds that cannot do Eden Park justice.
Some of the proposals in the plan make sense. Western Springs could produce a picturesque oval for test cricket with grass banks for spectators. Speedway would be better located in the industrial surrounds of Mt Smart. But tradition favours their existing venues too.
Retaining the status quo carries a considerable cost to ratepayers of an under-used Eden Park, but it is doubtful that revenue from reluctant league fans would make much difference. Eden Park is a luxury bequeathed to Auckland by national taxpayers for the Rugby World Cup. Auckland ratepayers can be grateful and resolve to maintain it for those rare, splendid occasions that will always make us glad to have it.