The conservatives this week retreated on a plan to replicate the Swedish "free schools" system, after an architect of the Scandinavian scheme said the cornerstone Tory policy would not work.
Michael Gove, shadow schools secretary, had predicted that allowing parents, charities and other organisations to set up "Swedish-style new academies" would, as in Sweden, lead to 15 per cent of pupils being educated at independent but state-funded schools.
"If we had Swedish-style reforms there is every reason to believe that we would have up to 3,000 new schools," he said last month. Other reports quoted figures as high as 5,000.
But Anders Hultin, a political adviser to the Swedish government that set up the free schools system in 1992, has said that because the Conservatives will not allow providers to make a profit from the schools this will be impossible.
When The TES put these concerns to Mr Gove at his party conference in Birmingham, he conceded: "There have been a lot of numbers bandied around and it may well be, because we are not allowing the profit motive, that they maybe different here."
Mr Hultin is a co-founder of Kunskapsskolan, the biggest Swedish free schools chain, which the Conservatives have been taking journalists to visit in Stockholm.
He argues the party has left out a crucial element of the Swedish model. "If they want 3,000 new schools the Conservatives must consider that more than 50 per cent of free schools in Sweden are run by for-profit companies," he said.
"Without the profit half of the free schools would disappear. If they are really keen to promote such schools in the UK, they must allow for-profit organisations."
The Conservatives also seem to have misunderstood another element of the system they have so much faith in.
Mr Gove says the Swedes have shown it is possible for free school operators to pay rent for their buildings out of exactly the same funding received by state schools, which don't pay for their premises.
In fact, as The TES reported last week, Mr Hultin says that Swedish free schools actually receive 15-20 per cent more funding than their municipal counterparts to take account of extra capital costs.
The shadow schools secretary also revealed his plans for even more academies, telling conference delegates that a Tory government would give the "best" comprehensives full academy freedoms.
The party believes around 400 schools that have either an overall "outstanding" judgment from Ofsted or a "good" verdict combined with an "outstanding" for leadership should qualify.
"We will be on course for academies to become the norm in secondary education," Mr Gove said. He later admitted to The TES this would mean most secondaries could ignore the new Conservative approach to the national curriculum he outlined in Birmingham for the first time.
It would emphasise the need for mastering English, maths and science and "demand that history is taught properly once more," he said to huge cheers. Earlier in his speech Mr Gove had criticised the Government for imposing central "diktats" on schools.