In practical terms, the argument about the Stillorgan Quality Bus Corridor is a silly one. The city's transport fathers decided as far back as 1994, in the final report of the Dublin Transportation Initiative, that building more and wider roads to facilitate ever more traffic is not sustainable - not to say furiously expensive and completely unjustified on a cost/benefit analysis.
In 1991 there were less than 200,000 cars on the roads, now there are 400,000 and that figure is going up by 200 every working day.
In short, the future has been decided: it has to be public transport all the way.
Owen Keegan, Dublin Corporation's director of traffic says the recent introduction of the Stillorgan QBC, coupled with the Malahide and Lucan QBCs, was not designed to punish the private motorist.
He argues instead that the measures - and there are a few more to be delivered yet - are designed to reward commuters making a choice in line with public policy, by opting to take the bus.
His opponents say Mr Keegan is simply being disingenuous. Giving preference to the buses is taking it from the private motorist whatever way you look at it. And Mr Keegan, conceding "some impact", counters that traffic jams are being caused by extra cars, not extra buses.
Over the past few months, even as the debate over the Stillorgan QBC was hotting up, the DTO was finalising its submission to Government for the largest investment in transport in the history of the state.
Included are £800 million worth of schemes for suburban rail, £428 million for Luas (excluding the underground costings which are not available yet), airport rail links, Dart extensions, new bus routes, buses and bus/rail interchange facilities, management systems and planning.