Gillian Shephard and the general secretary of the National Association of Schoolmasters Union of Women Teachers, Nigel de Gruchy, had their audience tittering into their agenda papers for more than a hour. And that was no mean feat. First, the subject material - class sizes, industrial action and Conservative education policies - hardly lends itself to comedy. Second, both managed to combine the mateyness with deadly serious political point-scoring.

After winning over her audience by talking about her gloomy dressing-room and lightly chiding the owner of a recalcitrant mobile phone, Mrs Shephard ran through the now familiar list of benefits that she believes the Government has bestowed on teachers in the past year.

She only needed the fingers of one hand to enumerate them: external marking of key stages 2 and 3 national curriculum tests and supply cover for key stage 1 assessment. A review of the flood of paperwork engulfing schools and - paradoxically - the publication of six circulars on pupil behaviour that were designed to improve discipline.

But she then departed from the basic speech she had delivered at the conferences of the Secondary Heads Association and the Association of Teachers and Lecturers and launched into what she later described as some “home truths”. Public respect for teachers was not as high in Britain as it was in other developed countries, a recent Organisation for Economic Co-operation and Dev-elopment survey had shown. “When I took on this job, the bolstering of teachers’ professional credibility was one of my primary concerns,” she says. “I am very aware of the hammering it took in the mid 1980s.

“It should be borne in mind there is united opposition to industrial action by teachers from parents, governors and political parties.”

Moreover, she said, class size was not a black-and-white issue, and then recited a list of variables - admission policies, popularity of a school, size of the year group, and availability of support staff (to name but four of the 15 she quoted).

Nigel de Gruchy nodded in agreement on this, but when he rose for his vote of thanks it became obvious that he too had a few home truths to deliver: “Secretary of State, I think we like you . . . shame you have to work for such a bloody awful Government.”

He also said he would prefer her to remain as education secretary than challenge John Major for the party leadership. “No chance,” she retorted cheerily.

And when he said bluntly “we are all aware that you or one of your accomplices leaked the letter” (about the effect of public spending cuts on the education service) it merely provoked a shake of the head.

But she did turn stony-faced when Mr de Gruchy criticised the Chancellor of the Exchequer, Kenneth Clarke and the Chief Secretary to the Treasury, Jonathan Aitken. And she was not amused when he responded to her complaint about the consequences of teacher action over large classes by saying: “What effect do you think 7,000 to 10,000 teacher redundancies will have? Don’t you think that creates some disruption, too?” Afterwards Mrs Shephard was overheard to admit that she was not entirely happy about all of Mr de Gruchy’s quips. The delegates, however, were.

And as far as Mr de Gruchy was concerned, that was all that mattered.