SABRE-rattling yet again, the biggest teaching union, the NUT, threatens industrial action over performance-related pay.

Delegates at their annual conference are claiming that the increased stress of assessment would be passed on by teachers to their pupils.

But even if this is not platform hype, there is likely to be precious little sympathy outside the conference hall for the reluctant teachers -- because virtually everywhere else workers are measured and paid according to their merits and agree with the system.

And what, after all, is wrong with the good and able teachers being rewarded with more pay?

Moreover what is right about the mediocre or lazy ones being paid the same as the better ones?