But the final decision should rest with Aucklanders. If a referendum at the 2013 local-body elections gave Mr Brown the go-ahead, the Government of the day should bow to this and provide the necessary approval for the Auckland Council to proceed with its financing plans.
For that to happen, however, Aucklanders will have to be persuaded that, as with the Auckland Harbour Bridge, the tolls they pay will be worthwhile. Most of all, they will have to be convinced that the rail loop will be attractive enough to garner solid patronage.
If so, road-users' interests will be served by an easing of traffic congestion. Additionally, Mr Brown will be keen to pitch the rail loop as a key to revitalising the city centre, thereby preventing urban sprawl.
The loop is a centrepiece of the draft Auckland Plan, the blueprint for the city's next 30 years. Unfortunately, the development of this plan is taking an alarmingly different tack from the inclusive mandate being sought by the mayor. At fault has been the schedule for public submissions, which has clashed with the Rugby World Cup. Unsurprisingly, given this distraction, the council had received only 143 submissions by Monday.
This is a farcically low response to a document of such importance. Before the timing problem became apparent, the council was expecting 2000 to 3000 public submissions, and was most concerned about how it could cater for the expected interest in formal hearings. Now, with October 25 being the submission deadline, it faces only embarrassment.
The council's hands seem to have been tied by the legislation setting up the Super City. Somehow those who drew this up were blissfully unaware either of the scheduling of a major sporting event or of its implications for popular participation in local governance. Equally, nobody else corrected their blunder in good time.
There are obvious perils if Aucklanders feel they have been denied a reasonable input into the Auckland Plan. They will not feel it is a truly democratic document that fairly incorporates their wishes and aspirations. As such, they will be less inclined to accept it.
This will rankle all the more as Auckland's mayor is prepared to show the courage of his convictions by putting his pet project to the ultimate popular vote.