Ask Barnaby Joyce for a cost-benefit analysis on moving public servants out of Canberra and it's likely the Deputy Prime Minister will talk a lot about the Sydney Opera House in reply.
The Nationals' leader regularly argues the landmark would never have been built if bean-counting bureaucrats had relied on economic models alone, along with other expensive projects like public transport networks and even federal Parliament.
"If you say we will premise everything purely and solely on cost-benefit analysis, I tell you what will happen," Mr Joyce said on Thursday.
"We wouldn't be having this press conference in Canberra because it would never exist. It wouldn't have passed the cost benefit analysis
"The Opera House? Forget about that. Fireworks displays on New Year's Day, there would be no cost benefit analysis that would allow that."
As the Coalition makes the case for forced moves of government agencies and public servants to rural and regional areas, leading economist Chris Richardson says the costs to Canberra could be great.
"At the same time as new technologies have led some people to say it no longer matters where people are, the evidence is increasingly going the other way," he said.
"It shows that people working in similar areas should rub shoulders as often as possible, they should see each other at the shops or walking down the street to grab a coffee."
Regular interactions help increase the value of big cities, what Mr Richardson calls "the most productive thing the human race has ever come up with".
The Deloitte Access Economics director said there was a strong case for keeping Canberra's policy functions in one place, warning individual assessments of any forced moves could miss the wider impact on the capital.
"It has different implications depending on which bits of Canberra's public service employment base you're talking about," he said.
On the Opera House, he said both costs and benefits are clear. Something in the order of $4.6 billion, based on a 2013 Deloitte Access assessment.
"You need to be careful with cost-benefit analysis, and if you do the sum right, chances are you would have built an Opera House.
"I think my favourite example is the inner-city rail loop in Sydney, which I use all the time. Of course a bunch of these things absolutely stand up.
"Do the sums right and that risk can in fact not be a risk at all," Mr Richardson said.