They’ll never pass for political Bobbsey twins. Stephen Harper and Jim Flaherty are more like the cabinet odd couple.

The prime minister is a pugnacious partisan who will bend or customize any policy in a non-stop bid to preserve and enhance his power in 2015.

His finance minister has no higher ambitions, is less preoccupied with trash-talking his rivals and is focused only on restoring his fiscal credibility before he retires with the deficit eliminated.

They are polar opposites on the social spectrum as well.

The prime minister is a teetotaler who shuns the gala scene except under wife Laureen’s orders. The finance minister can be the life of a party and has a tremendous capacity to bounce back from imbibing to excess.

Yet, despite all the yin and yang, this partnership worked spectacularly well for eight years and six days. Until Wednesday, that is. Around 10:30 a.m. eastern, if memory serves.

That’s when Flaherty decided to undermine his next budget by questioning the government’s key 2011 campaign promise to allow income splitting for families once the deficit is vanquished next year.

To let the well-off download $50,000 in before-tax earnings to lower-paid or stay-at-home spouses for a considerable tax savings always was a head-scratcher. It confers a lucrative benefit on the well-off and does nothing for couples with similar incomes and single parents.

To showcase that promise for three years before realizing it was a policy and political liability raises a lot of questions about the reputed genius of Conservative election strategists.  

Whatever the reason for the retreat – and there’s a gurgling whirlpool of spin from government sources that the two men are conspiring together to delete it from the 2015 election playbook  – Flaherty did himself and his boss a poorly-timed disservice. 

If the promise goes ahead now, Flaherty loses considerable face as a fiscal guru. If it dies, Harper has to campaign on why his party promoted bad policy as the voters' reward for budget balancing and stuck with it for so long.

This year’s truest bluest Conservative budget, sleepily prudent with only small targeted spending, was attracting reasonable reviews across the country.

Now, thanks to Flaherty’s musings at the worst possible moment, his balanced budget is still a year away and it is already being smeared and jeered.