The institute has previously backed a voluntary system and negotiated schemes with the 12 former regions, subsequently inherited by their 32 successor councils.
But ministers believe voluntarism has failed and details of the new regime were set out in a consultation paper issued last Friday. With Labour advocating appraisal and a strengthened role for the GTC in teacher development, any clear blue water between the parties has been reduced to a puddle.
Fred Forrester, the EIS's depute general secretary, confirmed the shift but said the decision was taken "on balance". It anticipates that the 50-member GTC, with 22 elected primary and secondary teachers, would briskly dispatch any scheme which was not teacher friendly.
"Appraisal must be driven by the needs of individual teachers," Mr Forrester said. "It must be a bottom-up rather than top-down approach, and that is dependent on a properly funded scheme. It also means that if any teacher is in need of in-service support, the training must be provided."
The consultation paper takes a cautious line, stating: "The Secretary of State believes that consideration should be given to giving the GTC a role in relation to appraisal, perhaps through advising the Secretary of State about local authority schemes submitted to him for approval."
The problem is that any extension of the GTC's powers will require substantive legislation to amend the Act which established the council. Appraisal, on the other hand, can be made statutory within six weeks if Parliament approves the draft regulations in line with powers the Government already has under section 70 of the Self-Governing Schools etc (Scotland) Act 1989.
A "tight but realistic" timetable for appraisal should allow councils to submit plans to the Scottish Office by July 16 after consultation with teaching staff. Schemes will have to show how each authority aims to begin the appraisal process for half its teachers on or before September 1 and extend it to the remainder a year later.
The requirement to submit to appraisal should become part of every teacher's contract of employment from September 1, the draft regulations suggest.
But Mr Forrester pointed out that the specific grant for staff development and in-service is to be subsumed within the general support for councils next month. "That is not a good omen for increasing expenditure on appraisal, " he said. "Many authorities have already put appraisal schemes on hold because of lack of money."
Inadequate funding would force councils to "cut corners", Mr Forrester feared. Proposals for teachers and their appraisers to receive advance training and for all 50,000 teachers to be given individual job descriptions contained major resource and workload implications, he said.
The Scottish Office has revealed, however, that a forthcoming report from the Inspectorate will show strong commitment by schools to staff development. Inspectors concluded that teachers who had been appraised found it was "beneficial". But the process is not "securely linked" to school development planning, they add.