So when Mary Bousted, ATL's general secretary, addressed her class on Monday, the audience was polite and attentive rather than boisterous.
Warning that the education bill would create "schools for the underclass", did not provoke the outrage that would be de rigeur at other union conferences.
Her defence of the union's social partnership with the Government was neither shouted down nor met with enthusiasm.
In fact the only applause during the first half of her speech to a two-thirds full auditorium in Gateshead came when she was interrupted by an announcement asking for the owner of a silver Peugot to return to their vehicle. "If it's any of you, you can see me after the event," Ms Bousted said.
Mild-mannered delegates, however, did create controversy in an attack on the national curriculum.
The ATL wants tests for under-16s scrapped and a system which concentrates on teaching skills rather than knowledge.
Ms Bousted said: "Personalised learning cannot exist in a system where children are tested to destruction."
When Jacqui Smith, schools minister, gave her speech, she had good news on the curriculum: pound;50 million would be made available to train staff to teach the vocational diploma courses proposed in the Government's 14-19 reforms.
She said it would help to ensure that, by 2015, nine out of ten remained in post-16 education and training. The first five of 14 diplomas will be available from 2008.
A motion saying public funding for new faith schools should be stopped by 2020 was passed. Delegates attacked the academies programme for allowing religious fundamentalists to take control of state schools. Ms Bousted said the union was not protesting against existing faith schools but was worried about current policies. But the ATL voted against a call for a ban on schools teaching creationism as a valid alternative to evolution.
It must be added that Ms Bousted's speech did eventually get her audience going. Attacks on lesson observations by heads nervous of Ofsted had delegates, if not on their feet, at least leaning forward in their chairs.
"Self evaluation is becoming self-inspection - with no feedback to teachers, no professional dialogue," she said.
"I warn Ofsted now, if you don't work with school leaders to stop this appalling practice you will drive thousands of good teachers away from the profession; you will lower standards of teaching and learning." For the middle classes as well as the underclass, she might have added.