Of course, it was good to see that Mr Blair rejects "crude payments by results", but it is this prospect that haunts the profession and continues to undermine morale.
Measuring and assessing teachers is not a precise science. It never can be. There are too many variables involved. A good teacher can perform admirably with a difficult class, and can make a genuine contribution to the social and intellectual development of a group which could never be assessed through statistics.
Someone else could teach like a dog and still the pupils would get fine examination results because of the innate ability of the class. And how is it possible to assess a teacher's contribution in a prosperous area where in some subjects it is the norm to pay for private tuition? Who is going to make these judgements? Teachers are notoriously contemptuous of management, who are seen as people who have run away from the classroom. I am a deputy head and I have been described as "a mouse training to be a rat". Often teachers are reluctant to let us make judgements, especially if we have a different subject specialism.
No, determining performance is difficult and divisive. If we are serious as a society in our wish to improve schools then what we should do is to listen to teachers and give them more time to do their job. What staff need is time to prepare for lessons, to use all the resources that are available in both primary and secondary schools. This is how you improve teaching, by enabling staff to work together to discuss the craft and the art of teaching.
More books and computers are vital, but teachers are the most important thing of all. We need a culture of support and co-operation, not threats.