Sealing the split
With the exception of public health, there aren't many Welsh government promotional campaigns more important than the one launched this week about Wales-only GCSEs.
There will inevitably be concern among parents that an education system which has performed so poorly in the Pisa international league tables is now going down the route of having its own bespoke GCSEs.
And those fears will be stoked by the decision of independent schools in Wales to go with the English exams and not the Welsh ones because they "lack credibility and portability".
And then throw into the mix the future possibility of the GCSE system becoming the kind of political football we've seen the state of the NHS become in recent months between a Conservative-led government in London and a Labour Welsh government in Cardiff.
It wouldn't do much for the prospects of young people in Wales up against English rivals in a highly competitive jobs market if the exams come in for the kind of criticism we've seen of Welsh health services.
Half empty half full
But that's the glass half empty attitude. There is the glass half full version which sees this as a great opportunity for the Welsh education system.
Of course we've had different people running schools in Wales and England since the start of devolution but pupils on either side of the border have always come out the other side with the same qualification.
So there was always a leveller at the end of the process in the eyes of employers and universities.
But that's all about to change and in effect the split in the two education systems will now be sealed with an end to the shared qualification.
How did we get to this?
Gove v Andrews
You could argue that the divergence in Welsh and English GCSEs will be one of the most significant and lasting results of having two politically different governments on either side of the M4.
Before David Cameron became Prime Minister in 2010 there had been Labour governments largely enjoying a benign relationship since the start of devolution.
That all changed pretty quickly and, before Drakeford v Hunt became the biggest draw in town, it's worth remembering that Gove v Andrews was top billing when they were in charge of their respective education briefs. Both have now moved on.
The row over the grading of GCSE English papers in 2012 and the big shake-up of the exam system in England by the then Conservative education secretary Michael Gove - which included the removal of coursework - formed the backdrop to the split.
That split was then formalised by the findings of an independent review of qualifications that had been ordered by the Welsh government.
I suppose the changes could have happened anyway, but there's no doubt that Labour/Tory row speeded up the divergence.
Numeracy and literacy
So what happens next?
The first pupils will begin the new GCSEs next September in maths, English and Welsh. They'll sit the first exams in the summer of 2017. Most of the rest of the subjects will follow a year later.
The focus will be on numeracy and literacy but, unlike in England, coursework will be retained.
There will be changes to other exams but there will be less of a difference between Wales and England when it comes to A level courses which will share the same content as far as possible.
With big changes ahead, the job of ministers and officials is to try to get the message across that these are changes that parents should not fear.