You can tell how bad Tony Abbott’s evening press conference on negotiations with the independents was yesterday by two indicators: the transcript remains unreleased by his office, and Dennis Shanahan today issued News Limited’s ukase that a new election be held to put a stop all this nonsense.

By the way, if you want conspiracy theories, why didn’t ABC News 24 broadcast it? Were they keen to ensure Abbott’s embarrassment, including his sudden departure under a hail of question from journalists, wasn’t publicly displayed?

It’s extraordinary just how much the Charter of Budget Honesty, a mechanism developed by Peter Costello to undermine Labor, has come back to haunt the man Peter Costello rated so poorly on economics. The Coalition refused to provide its policies for costing by Treasury during the election campaign and now, remarkably, refuses to provide them to Treasury after the election to enable the independents to assess the impact of the parties’ policies on the Budget.

Conservatives online have tried to portray Abbott as bravely holding out against the outrageous demands of the independents. In fact, Abbott has agreed to all the other demands of the independents, including surrendering the traditional prerogative of the prime minister to decide when an election will be held. It is only in refusing to adhere to the requirements of the Coalition’s own Charter of Budget Honesty that Abbott is making any sort of stand.

His reasoning for doing so seems to be two-fold. Last night it was because the public service, somehow, wouldn’t “understand” the Coalition’s policies. Quite what that even means is a complete mystery. Who did the Coalition think was going to implement their policies? Were they intending to outsource delivery of their policies to accounting firms?

This morning, talking to the ABC, Abbott had entirely changed his excuse, back to the claim that since there was a leak during the election campaign the Coalition couldn’t trust Treasury until the leaker was found and removed. This ‘Bring Me The Head of Alfredo Shinybum’ stuff is equally confusing. Even adopting the Coalition’s feigned outrage about the original leak (because it never leaked material to damage its opponents when in government, as Andrew Wilkie might be able to attest), what is there now to leak anyway? Isn’t the entire point to see what the Coalition’s policies would cost?

“I can’t see why we cannot conclude anything other than that you are scared that Treasury will find gaping holes in your costings,” said The West Australian’s Andrew Probyn to Abbott last night. It was the money question in a press conference in which Abbott had few answers and was hammered by journalists before he fled.

This can be spun all sorts of ways by the Coalition and its apologists but there’s a basic issue here: the Coalition is scared of having Treasury examine its policies and desperately reaching for any excuse as to why it shouldn’t. How on earth does that makes them a credible party to form a government?

Treasury may well find errors in the costings that reflect the reality that oppositions can’t match the modelling firepower of the bureaucracy. Such errors are entirely understandable and are unlikely to be particularly large anyway. By my count, the Opposition was well ahead of Labor in terms of the fiscal impact of its commitments, which had Labor over $2 billion in the red by election day.

But it appears the Coalition is worried there are bigger problems lurking in their policies. The fact that they took their costings to a private accounting firm many weeks before the leak that they allege was the reason for avoiding Treasury suggests that may indeed be the case.

More to the point for where this interregnum is going to end up, Abbott continues to stumble in his handling of a hung parliament in which he must surely be strongly placed to obtain the support of the rural independents. While Julia Gillard is giving the independents anything they ask for in a desperate effort to cling to power, Abbott seems to think the prime ministership should fall to him by right.

I’ve said before the problem is less Abbott’s grasp of economics than his temperament. Last night confirmed that.