By Ken Macdonald
BBC Newsnight Scotland correspondent
Appeals against this year's examination results could be reduced under a new system introduced by the Scottish Qualifications Authority (SQA).
The marking process is said to be under strain
Last year there were more than 85,000 appeals against poor results and the SQA said that the process was under "great strain".
It has told schools and colleges that any examination centre wishing to submit an appeal for 10% or more of candidates in any single course must provide "a written rationale explaining the exceptional circumstances".
While teachers' leaders conceded there was a problem, they said it was the wrong solution and that it would only add to bureaucracy.
In a letter from SQA National Qualifications General manager Tom Drake, schools were warned that appeals should only be made where there is "clear evidence" that pupils are able to perform "significantly" better than their exam result indicate.
It warned that the number of appeals had "risen markedly" in recent years putting "great strain on the system and particularly on the teachers and lecturers who process them".
In 2001, the latest year for which full statistics are available, about 12% of results were appealed at Intermediate one and two levels, while at Higher the rate was 16%.
At Advanced Higher, the appeal rate was 16.4%.
At least a third of all these appeals resulted in an upgrade, but the SQA's new cut off point is just 10%.
The Scottish Secondary Teachers' Association (SSTA) said the SQA had come up with the wrong solution.
SSTA president Alan McKenzie said: "It is another layer of bureaucracy.
"It probably will make little difference to the upward pressure from parents and pupils, and will simply create another hurdle that teachers have got to get over in August when they are submitting appeals.
"I don't think it will lead to a reduction in work at all. It will lead, I think, to an increase in the amount of work for centres and teachers."
He said it would be better to persuade pupils and their parents they can trust the results.
Head teacher Jim Cunningham, who is a member of the SQA's task group on national qualifications, said that the fallout from the exams fiasco in 2000 was still being felt.
Memories are still fresh about the debacle which left thousands of pupils with late or incorrect results.
Mr Cunningham said: "Parents maybe suspect that the exam system has creaked before and it could creak again, and maybe it is creaking for their child."
He also said that pressure for appeals came from larger numbers of pupils taking the new Advanced and Intermediate exams and from the pressures created by school league tables.
The SQA said its system already contains, in effect, an automatic appeals process, meaning some pupils' results are upgraded before they get their certificates.
Meanwhile, hundreds of Scottish teachers are expected to be told on Wednesday morning that they are overpaid.
Principal teachers and other holders of promoted posts have been subjected to a "job-sizing" exercise as part of the McCrone deal on pay and conditions.
Some will get pay rises as a result - but as many as two-thirds may be told they are getting too much.
And while the allegedly overpaid teachers will not have their salaries cut, some believe it could damage staffroom morale.