George Osborne is a dab hand at sales patter. Arriving as chancellor four years ago, his aim was to hammer home the idea that all the problems of the economy were the fault of the previous Labour government. The line was that Gordon Brown had "failed to mend the roof while the sun was shining".

That worked well. To this day, opinion polls show voters think Labour was to blame for the cataclysm that befell the economy in 2008.

The chancellor's next soundbite was "we are all in this together". The intention here was to show that the pain of coping with the legacy of Labour would be shared. This was less potent politically. In part that was because the economy stalled soon after Osborne moved into the Treasury and moved sideways for two years afterwards. In part, it was because the public took one look at the cabinet and decided that "posh boys" did not really understand what belt-tightening was all about.

Now we are into Osborne 3.0. The message now is that the long-term plan is working and Britain must stick to it. In the 11 months that remain before the next general election, the idea is to draw all the themes together in one narrative: Labour screwed up the economy and that required Britain as a nation to make sacrifices. But staying the course has been worth it. Abandoning the plan now would mean handing power back the clueless bunch that made such a mess of things in the first place.

One obvious flaw with Osborne's narrative is that the government doesn't really have a long term plan. It used to have a long-term plan based around export drives, investment and a new model of growth that did not rely on consumer debt. Now it has a short-term plan to keep the economy going at full throttle until polling day.

Let's examine some of the evidence, starting with the Conservative party manifesto of 2010. This said: "A sustainable recovery must be driven by growth in exports." There is nothing wrong with that sentiment. Indeed, given that the UK has run a visible trade deficit every year for more than three decades, it is an entirely laudable objective. But despite the boost from a 30% depreciation of sterling between the middle of 2007 and early 2009, it has not been delivered. The trade figures remain stubbornly in the red, while the broader current account – which takes into account investment income – is running a deficit of 5.5% of national output.

In his first budget, in June 2010, the new chancellor fleshed out his plans. He would slash government borrowing over the next five years while building an entirely different sort of economic model. "Our policy is to raise from the ruins of an economy built on debt a new, balanced economy where we save, invest and export."

Again, nothing to quibble with there. But the years of flatlining have meant that Osborne has missed his deficit reduction targets by a mile. In that first budget speech he said net borrowing would be £37bn in the current year. The latest forecasts from the Office for Budget Responsibility put it at close to £100bn.

Nor has there been a pickup in private investment during this parliament. When adjusted for depreciation and dilapidation, capital formation by the non-financial private sector stood at £43bn in 2008. It then halved to £21bn in 2009, then carried on falling to just over £14bn – less than 1% of GDP – in 2013. In recent quarters there has been a modest pickup in private capital spending, but there is a mountain to climb. The lack of investment for the past six years helps explain why productivity is so weak.

As for the idea that the new government wanted nothing to do with the failed debt-sodden splurges of unsustainable growth Britain has seen in the past, that resolve did not last much beyond mid-term, when the Conservative party started to count down the days to May 2015. Government borrowing targets were quietly (and sensibly) amended to make them less onerous. The Funding for Lending scheme provided banks with incentives to lend to the mortgage market (eagerly seized) and to small businesses (not so eagerly seized). And a new governor of the Bank of England arrived with a message for borrowers that they didn't have to worry about interest rates going up any time soon.

In the circumstances, it is hardly surprising that the housing market is going gangbusters. Nor is it that remarkable that the economy is growing at just over 3%, given the fact that official borrowing costs have been at 0.5% for more than five years. In normal circumstances, the economy can be expected to grow by around 2% a year due to population growth and technological advance. Rather more noteworthy is why, under Osborne's stewardship, an economy that was growing at an annual rate of around 2% in the spring of 2010 has taken so long to recoup the ground lost in the recession.

Strong growth will continue between now and the election. It may even result in a rise in real incomes. But as with investment, it will not be nearly enough to compensate for what has happened since 2008. National output will get back to its pre-recession levels in the current quarter, but that is only because the population has been rising. Real disposable incomes per head are well down on where they were when the recession began and even now wages are struggling to keep pace with prices.

Osborne has two things going for him. The first is that unless the Bank of England overdoes measures to cool down the property market, the economy will remain strong for the next 12 months. The second is that the opposition is making such a feeble fist of things. Osborne only really has a short-term plan, but at least he has a plan of some description. Labour has a collection of policies, some of them attractive ones, but it has to bring them together in a coherent and convincing strategy.

Opinion polls reflect this. Some voters may see Osborne as a snake oil salesman arriving in town in a covered wagon to dispense potions at a medicine show. But they see Ed Balls as even more of a quack doctor.

Labour was badly damaged early on in this parliament by Osborne's ability to get his version of politics accepted as the received wisdom. It is in danger of being caught flat-footed again, although it doesn't need to be.

Why? Because the short-term nature of government economic policy provides Labour with the opportunity to lay out a genuine long-term plan for how Britain kicks the mortgage-debt habit, retools industry, rewards work, and pays its way in the world. But it needs to sharpen up its act, and quickly.