Suspicions that plans for 100 skills academies across Scotland, announced by First Minister Jack McConnell in a speech to the Labour Party's UK conference last September, were causing a rift between the two parties deepened during the debate, which was initiated by the Tories.
Murdo Fraser, the Tories' spokesman, pointed out that the Scottish Executive's amendment did not even mention skills academies, which his party supports.
Robert Brown, the Deputy Education Minister and prominent Liberal Democrat, who opened for the executive, simply rehearsed the steps it had already taken to improve vocational choices for young people, such as closer school-college links and skills for work courses.
Mr Brown's amendment side-stepped the term "skills academies" and referred to "steadily improving opportunities... to study a wider range of vocational options".
His party colleague Iain Smith, a former minister who is convener of the parliament's education committee, was more direct. "Skills academies are not the right way forward," he said. "We must continue to invest in broad-based education in Scotland, from pre-school right through to provision for 18-year-olds."
Mr Brown later explained his party's coolness to skills academies by suggesting the idea was floated by Mr McConnell in his capacity as leader of the Labour Party, not as First Minister.
But Lord James Douglas-Hamilton, winding up the debate for the Conservatives, countered that Mr McConnell was "laying down the policy for the coalition".
Labour MSPs endorsed the proposals, but acknowledged the risk of creating a two-tier system.
This was the focus of the SNP's emphasis, its amendment arguing that "all children should have vocational opportunities and that these should not be restricted by assessment of academic ability at the age of 14".