An immediate federal election is the last thing we need unless we're happy for it to be a fiscal lucky dip. Both sides have much work to do yet to provide voters with adequate information on the cost of their policies and election promises and how they'll be paid for.
Labor must deliver this mainly in the budget; the Coalition must release its facts and figuring no later than early in the election campaign proper. And don't be in any doubt: it's a tall order for each of them.
There are three reasons why this is so.
First, both sides say they're committed to returning the budget to surplus during the next term of Parliament, with the Libs claiming to be able to do it earlier and better than Labor.
Second, the relatively recently discovered structural weakness on the revenue side of the budget is a problem for either side.
It will be a particular problem for the side that wins the election, of course. But, to the extent Treasury takes account of this weakness in its revenue forecasts and projections in the budget and the pre-election update, it will be a problem for both sides during the campaign.
Third, in their very different ways, both sides have made some very expensive promises. So, at a time when revenue growth is likely to be unusually weak, both sides are promising to be particularly generous in increasing spending or cutting taxes, while also losing little time in returning the budget to surplus.
To remind you, company tax, the mining tax and other taxes on profits are being hit by the fall in export prices, plus the dollar's failure to drop down as expected. Income tax collections are being hit by the way eight tax cuts in a row have reduced the extent of bracket creep.
And collections from the GST are being hit by the end of the era where consumer spending grew much faster than household incomes and by the shift in spending towards those items excluded from the tax, particularly private health and education spending.
In theory, this is a problem for the states, not the feds. In reality, all major revenue problems common to the states end up on the feds' plate.
Because Labor's in government, and because most of its big promises are already enshrined in legislation, its moment of truth will come in the budget. In particular, it will have to demonstrate convincingly how it will cover the cost of the twin centrepieces of Julia Gillard's re-election pitch: the National Disability Insurance Scheme (costing about $8 billion a year by 2018) and the Gonski education-funding reforms (costing about $6.5 billion a year by the end of the decade).
Gillard and Wayne Swan have promised to spell out in the budget the "structural savings" they will make to fully fund this additional spending. "Savings" may include reductions in tax concessions ("tax expenditures") as well as cuts in conventional expenditure, but "structural" means the savings must continue - and grow - over many years.
Rest assured, the opposition and the commentariat will hold Labor to account on this score. And one thing this means is that it won't be nearly sufficient for Swan to show how these two ever-more-expensive policies will be funded merely for the coming four years. If it takes up to six years for them to reach their full yearly cost, that's how far into the future Swan's figures must go to show he has that cost covered.
Further, credibility will be attained only if, unlike the past two or three budgets, this one involves no resort to creative accounting: no shifting of spending from the budget year back to the previous, almost-ended year, no use of Swan's "fiscal bulldozer" to push spending commitments off beyond the forward estimates where they can't be seen, and no exploitation of loopholes in the definition of the underlying cash balance, including funding spending on the national broadband network off-budget.
As for the Coalition, if it is to come clean with voters there must be no repetition of its utterly dishonest performance in the 2010 election campaign, where it refused to have any of its promises properly costed by the econocrats, claimed its costings had been "audited" by an accounting firm when it had done little more than check the arithmetic, and only after the election was revealed to have published costings that were wrong by up to $11 billion.
This time, there will be no excuse if the Coalition fails to use the services of the Parliamentary Budget Office. And with all the provisions of its own charter of budget honesty in operation, should it try the old stunt about being shocked to discover a big black hole when it saw the books, we'll know it is fudging. It won't be Ju-liar, it will be Tony-liar.