As ministers released figures showing a slight downturn in last summer's Highers' performance, the union claimed there was "an explosion of anger" among unpromoted teachers about the Higher Still assessment methods. The programme is due to begin in August 1999.
Many unpromoted teachers were only now beginning to look in depth at the Higher Still documents and were realising the burden of assessment. Higher Still planners and trainers were also refusing to listen to criticism of content or assessment, "however justified".
There is a real risk the programme will be "so deeply flawed as to lack credibility", according to Fred Forrester, deputy general secretary.
The EIS predicts the numbers of young people gaining a Higher award will fall as candidates will have to pass each course unit before they receive a certificate. Pupils are likely to use the extra hours of teaching time in the course design to resit units they failed previously.
Some who currently achieve a Higher pass will not gain an award in the revised format, according to Mr Forrester, who has written to Douglas Osler, senior chief inspector of schools, to underline teachers' concerns.
Teaching would be damaged as teachers come under "moral and emotional pressure" from families to allow repeated reassessment and teachers would be forced to spend time monitoring tests. "Many of the welcome improvements in terms of developing independent study skills, confidence and responsibility would be set at risk by this," the union states.
The stress on assessment in each unit will also switch the focus away from learning in areas not immediately identifiable as subject-related knowledge and skills. "In this sense," Mr Forrester says, "Higher Still courses will become assessment rather than curriculum-driven. Candidates will be tempted to spend time preparing for assessment and test-taking rather than on learning."
The EIS cautions that candidates may achieve several but not all the learning outcomes in a unit or several but not all the performance criteria. "It is evident that a candidate precluded from a course award by such a limited level of failure is likely to feel ill-used and indeed demotivated," it points out.
Mr Forrester believes Higher Still will place even greater stress on pupils who already report increased pressure in fifth year. "There is little doubt, " he maintains, "that many candidates will perceive the total burden of summative assessment to be greatly increased.
"Motivation for learning will be inhibited even where a candidate has passed all the unit assessments. The effects on candidates who have failed an early unit assessment are readily imagined."