Yet another new style of Ofsted inspections is on its way, and things are likely to get tougher for schools as the watchdog continues its bid to "raise the bar". The question that has troubled heads' leaders for months is how much tougher? And which schools will be affected most?
The answer might have been expected a fortnight ago when Christine Gilbert, the chief inspector, announced details of the long-awaited framework which is to be introduced in September. But the one detail schools were desperate to hear - exactly how inspectors would be judging their academic achievement - was conspicuous by its absence.
Ofsted announced its proposal to put more emphasis on raw exam results - unadjusted for pupil background when judging schools - more than a year ago.
But how this would work remained a mystery for so long that the Association of School and College Leaders last month warned of high anxiety among heads, who would be "victims" in new-style inspections because of they lacked advance knowledge.
Days before the framework was unveiled, Ms Gilbert said in an interview with The TES that there would be greater emphasis on raw results, or "attainment". But she sought to reassure schools with "poor" results.
"If they were really improving and the capacity in the school was strong, and you could demonstrate good progress for the pupils - that is the key thing - you could certainly still get a good evaluation, a good assessment overall," she said.
But when asked, in the week in which the new framework was announced, to define "poor", the chief inspector seemed unclear.
"I don't know in the end . In the pilots, two things were tried," she said. "There is a debate about whether it is averages, attainment linked to national averages, or whether it is linked to thresholds - the 30 per cent National Challenge, that sort of thing."
That internal debate seems to have ended in a score draw, with both definitions used.
A week later, Ofsted said final year raw results that have been "significantly below average" for three years would be deemed "low" attainment, but added that in reaching this judgment, inspectors should also consider "National Challenge benchmarks" - presumably the target of 30 per cent five A*-C GCSEs including maths and English, set by the Government for its controversial school improvement scheme.
The mention of National Challenge will raise alarm among hundreds of heads still smarting at the threats of closure because their schools' results did not cross this arbitrary threshold, regardless of pupils' backgrounds and progress.
But the use of averages in deciding what is "low" could be even more damaging. Average is by definition a relative term that says nothing about the absolute quality of the teaching in a school, particularly when applied to raw results.
All schools might improve hugely, way above the National Challenge benchmark, and there could still be some with results "significantly below" the new national average.
The current boom in hiring private tutors among professional parents is likely to mean schools with middle-class intakes pulling away from those serving poorer areas.
Schools where parents cannot afford to pay for extra tuition could find their results falling further behind the national average because of something that takes place outside the school system. They could now also be penalised by Ofsted - with heads potentially losing their jobs - for something over which they have no control.
Ms Gilbert admitted things would be "tougher" from September. "If you had poor raw data and, say, satisfactory progress, you wouldn't be able to get a `good'," she said. "You wouldn't be able to do well."
In fact, it is tougher than that. Ofsted has revealed that schools with "low" raw exam results, where progress is no better than "satisfactory" and there is little evidence of improvement, will automatically be placed in special measures or given a formal notice to improve. And the chief inspector's reassurance that schools with "poor" raw exam results where pupil progress is good can get "good" overall judgments seems a touch optimistic.
Inspectors' verdict on attainment, or raw results, is combined with a judgment on the "quality of pupils' learning and their progress" to give a pupil-achievement grade.
From September, to get an "outstanding" achievement grade, attainment must be at least "above average". Crucially, schools where attainment is "low" will not be able to get a "good" grade or better except in "the most exceptional circumstances", according to Ofsted's evaluation schedule.
But achievement must in turn be at least "good" to produce a grade for "outcomes for individuals and groups of pupils" that is "good" or "outstanding". The outcomes grade then feeds into the overall grade and must be at least "good" if the school is to achieve a grade of "good" or better.
Mick Brookes, general secretary of the National Association of Head Teachers, blames the Department for Children, Schools and Families for an "unacceptable" situation. He says he spoke to a senior official in the department while the framework was being developed who said the shift in emphasis was needed.
"It is quite clearly a nonsense," he said. "It further demoralises those schools working as hard as any other school to raise standards."
But Mr Brookes is just as concerned about the use of contextual value- added measures in Ofsted judgments of progress: he believes the measure, designed to show how much schools actually contribute to pupils' advancement, "doesn't actually work". He argues that grammar schools with pupils who arrive at the school at one level above the expected national curriculum level of achievement have ended up with "satisfactory" ratings, even if their pupils gain A* at GCSE.
Conversely, Mr Brookes says pupils with learning difficulties will struggle to make the progress expected of pupils generally, even though they start at a low level.
One aspect of the new framework that Ms Gilbert does expect to be welcomed by school leaders is the chance for them to have more involvement in the inspection process. From September, all heads will be invited to give their views of the issues for the inspection before it begins, take part with inspectors in lesson observations, attend formal inspection meetings and discuss inspectors' recommendations.
The chief inspector explains: "Say the literacy is weak: there might well be a debate between the staff and the inspectors about what is needed to move that school on. You know - should they focus on a phonics course? The recommendations would capture some of the detail about that."
Although Ms Gilbert stresses they will remain "very much the inspectors' recommendations", schools will be able to influence them. All school staff should also be able to make their views known during inspections if they choose to take part in voluntary surveys.
But it is parents, rather than teachers, whose hand will be strengthened most. It was parents' fears that they would be unable to give their views to inspectors that persuaded Ms Gilbert not to proceed with no-notice inspections for all schools.
For the first time, schools are to be judged on the effectiveness of their engagement with parents. And it is the views of parents, now to be collected for risk assessments between inspections, that could trigger earlier or extra visits from Ofsted.
"If parental perceptions of a school plummeted in a year, we wouldn't necessarily go in to inspect, but we probably would if it was low the following year as well," the chief inspector said.
John Dunford, general secretary of the ASCL, notes that schools already carry out surveys of parents as part of their self-evaluation. He argues that by setting up its own surveys, Ofsted has shown a "regrettable lack of trust in schools".
But with the watchdog considering a plan to allow pupils' views to trigger inspections - something that unions feel could leave schools at the mercy of disruptive pupils with an agenda - there could be worse to come.
When the inspectors call
Most "good" and "outstanding" schools will inspected every five years, with publication of interim assessments in between.
Greater emphasis on raw results and National Challenge targets.
End of light-touch inspections: all visits will last two days.
Most schools will be given shorter notice of visits: between nought and two days.
Eightfold increase in the number of "satisfactory" schools receiving monitoring visits.
New judgment on the use of assessment to support learning.
Doubling of time spent observing lessons during inspections.
More dialogue between schools and inspectors, with joint lesson observations and heads able to attend inspectors' meetings to hear how judgments are reached.
Increased emphasis on the five Every Child Matters outcomes.
Streamlined self-evaluation forms.