Given the enormous demands on schools, and especially their leaders, a credible, rigorous and honest system of external audit is crucial, but Ofsted surely cannot provide it. Conceived in the period of Bakeresque reform, it started badly and the leadership of Chris Woodhead was inextricably marred by the autocratic self-aggrandisement which characterised his style.
Good schools are marked by teamwork, honest and constructive criticism and the building up of confidence and best practice. Ofsted's great flaw has always been that it is "done" to schools, often as a form of educational "mugging". It can inflict real damage to an organisation and then walk away without providing either support for solving real problems or any genuine redress where the inspection has been flawed: a true example of real power without responsibility.
The latest framework of short inspection makes the situation worse. While good Ofsted teams have always existed, poor or lazy teams can now hide behind selective Panda or Family Fischer Trust data.
At its worst a school may well, if the data says that its front door is green, have to spend half a day proving empirically that the door is blue.
The suspicion is that regularly changing the inspection format is more about justifying the existence and expense of running Ofsted than helping schools to improve.
Christine Gilbert may well do a great job, but Ofsted is now a brand name which has little credibility with schools and little respect or affection from them.
Most schools believe that Ofsted will "get you" one way or another , and no matter how well you may perform, there will always be something to criticise. This is what is killing the real step forward of self-evaluation.
The ultimate disgrace is the two-day-notice phone call which is causing so many heads extra stress when they have more important things to do.
Charitably, one should wish Christine Gilbert well, but this correspondent cannot find it in his heart to do so when the organisation she will be leading has so little "street cred" with the recipients of its work and is so much past its sell-by date.
144 Cop Lane