The council's meeting in Falkirk last week was told by Malcolm MacKenzie, senior lecturer in education at Glasgow University, that the education White Paper offered opportunities the council had been seeking for years.
Mr MacKenzie warned: "If we torpedo this by some of the mealy-mouthed attitudes I have heard expressed here today we will throw away the chance we have been waiting for. The subtext I have been hearing from a lot of the vague comments is 'we don't like appraisal so we don't want anything to do with it'.
"But no matter the outcome of the general election, appraisal will be introduced whether we like it or not. The cushy days are over and, if the GTC does not set the agenda for appraisal, we will go back to the days when we were just a bunch of nice people who met occasionally."
The White Paper envisages the council having extended powers to deal with appraisal, staff development beyond the two-year probationary period and the striking of incompetent teachers from the register. Labour has put forward similar proposals.
Mr MacKenzie, a vice-chairman of the Tory Reform Group in Scotland, agreed that some of the ideas in the White Paper required more work, particularly the apparent confusion between staff development and appraisal. But his central remarks were directed at council members who expressed concern that the council might be in danger of following the Government's agenda and not serving the interests of the profession.
Graham Dane, head of physics at St Augustine's High in Edinburgh, said the "sledgehammer of the GTC should not be used to penalise incompetence, which should be handled at a lower level by the local authorities".
Mr Dane, a member of the national executive council of the Educational Institute of Scotland, said other professional bodies distinguished between malpractice and incompetence "and we should not blur the two".
Marie Allan, convener of the probation committee and past president of the Scottish Secondary Teachers' Association, also urged caution in embracing "a political task of dismissing all those thousands of incompetent teachers who are supposed to be out there because the education authorities allegedly did not do it".
Tony Finn, the council's education convener, took issue with the "narrow and negative" tone towards appraisal adopted in the consultative paper.
Local authorities also oppose an extension of the GTC's powers but for different reasons because they see such a move as an encroachment. Anne Wilson, director of education in Dundee and general secretary of the Association of Directors of Education, made a carefully worded intervention urging the council to work with the authorities to ensure their respective roles did not "overlap".