In the decade prior to 2010, Wales took a different route from that of England, and from much of the world. An insecure Welsh Assembly was anxious to show quick and popular results after the devolution of power in 1999, and avoided following any of the apparently unpopular education policies of England. Wales used to publish a national "league table" for all secondary school exam results - that was scrapped. Primary schools never had their results published in the first place.
The multiplicity of kinds of schools that England had - academies, comprehensives, specialist schools, grammar schools - was anathema to Wales. Instead, there was a commitment to community comprehensives. England had national targets for examination achievements - Wales had them, but considered it a bit vulgar to ever mention them. England used parents and performance data to pressure its schools - schools in Wales were trusted to deliver. The hated external Sats were abandoned and replaced by moderated school-based assessment at the ages of seven, 11 and 14.
The publication of the Programme for International Student Assessment (Pisa) results last December showed where this had landed Wales. In 2007, we had been below the other home nations of England, Scotland and Northern Ireland - that was shock enough to a nation where "Welsh" and "educated" were regarded as synonymous. But by 2010 we had sunk well below the other three nations, to a level on a par with that educational hothouse of Greece, in the case of mathematics.
The arrival of a new education minister - Leighton Andrews - in 2010 changed everything. In a series of policies announced from spring 2011, Wales was tasked with adopting the simultaneous "demand side" and "supply side" policies used in other countries. The emphasis was on national strategies of continuing professional development, national testing, reform of local authorities and - of course - publication of performance data.
But the Welsh performance data will not be published in national league tables, as it is in England. Instead, all secondary schools have been put into one of five "bands" based on a wide range of performance data: raw achievement scores, value-added scores, attendance rates. All 220 secondaries have been told their provisional scores, and their confirmed results will be published nationally in December. Primary schools will follow into the banding system, although the mechanisms of their system are still being discussed - there are concerns about the validity of the key stage 2 assessments, which in Wales are school-determined, and small numbers of pupils from our large number of small schools creates problems.
Banding is designed to differentiate schools sensibly so they can receive differentiated policies - the "top" band is seen as helping the other bands, with other bands receiving a higher and higher level of support as their bands worsen. Little has been said about whether the bands are to influence parents. But they do reflect a wider range of data than the English league tables.
In any case, the Freedom of Information Act means that performance data cannot be held back any more - BBC Wales published the value-added data for all secondary schools to great interest this spring. There is no doubt that taking multiple indicators and turning them into an overall band score is not straightforward. What are the loadings to be? The difference between the top of one band and the bottom of the next band may be numerically small, but unless the individual school scores are published together with the overall bands no one will know this. Union opinion would be heavily against this, though, and it may not happen.
New solutions to age-old problems
How powerful an initiative is banding if it is operating on "supply" of education only? The competitive advantage to England over Wales of a couple of GCSE grades per pupil, shown in research by Simon Burgess of Bristol University, is probably because the English league tables influenced parental "demand" and encouraged parents to shop around between schools.
In Wales, there is no desire for banding to be used in this way. Even if there were, many parents in Wales can do nothing about their choice of school because there is only one local school within reasonable travelling distance for their children.
Is banding the power of the league tables without the pain? Can enough leverage be achieved if the bands influence the support to schools but not the parental pressure? Will the difficulty of turning multiple indicators into one overall band lead to trouble in a litigious world?
Many of the initiatives in Wales, like banding, represent new solutions to age-old problems. How do we build capacity in our teachers? Wales is bringing the world's great knowledge bases to teachers electronically. How do we build capacity at system level? Wales will have ambitious training programmes for system leaders. How do we involve professionals? Wales is ambitiously setting up professional learning committees in every school.
Will all this - with banding - work in the long term? The Pisa results in 2013 and 2016 should give us a clue.
David Reynolds is professor of educational effectiveness at Southampton University and senior policy adviser to the Department for Education and Skills in the Welsh Government.