It is now more than three years since the National Union of Teachers refused to sign the workforce agreement because it feared a greater role for teaching assistants would cost qualified teachers their jobs.
During that time, the Government has introduced guaranteed non-contact time for teachers, the number of support staff has rocketed and the number of pupils in primary schools has fallen by 150,000.
But figures published this week suggest that falling rolls and allowing teaching assistants to take classes have done little to undermine teachers'
Primary heads may have complained they could not afford the extra staff needed to implement the 10 per cent planning, preparation and assessment time introduced last September, but they still managed to employ an additional 2,100 full-time teachers.
Secondary teacher numbers are also increasing, despite their rolls also starting to fall.
That is not to say the introduction of PPA has been easy. Many primary heads have been forced to spend more time in the classroom, while even secondaries have had to find novel ways to free up teacher time.
Duncan Fleet, headteacher of Culverhay school in Bath, was recently forced to defend his decision to introduce skateboarding lessons for pupils as a way of giving teachers time away from class.
But with the evidence suggesting its worst fears have not been realised, is it time for the NUT to drop its opposition to teaching assistants taking classes alone?
Mary Bousted, general secretary of the Association of Teachers and Lecturers, said: "This vindicates our position and leaves the NUT's opposition in tatters. All their gloom and doom about anarchy in the UK, standards plummeting and teachers losing their jobs has been proved to be untrue. How long can the NUT continue to scaremonger when they are being proved repeatedly wrong?"
Unsurprisingly, the NUT believes the figures do not tell the whole story.
John Bangs, the union's head of education, said: "Supply teachers are not included in these figures. Our casework suggests their numbers have gone through the floor."
This assertion is disputed by the ATL, whose own recent survey suggests supply teachers have not lost out.
Mr Bangs said tighter funding will inevitably place permanent staff in the line of fire. "The current very welcome cushion of funding provided by Gordon Brown has tended to remove the potential impact of the agreement.
You will see the effect in a cuts situation,"he said.
NAHT conference 15