The report raises a number of other issues which are of wider and more controversial significance, including reviving the proposal previously rejected by the unions of a fast track allowing pupils to sit their Standard grade exams before S4.
The present age restrictions should be reviewed, HMI recommends.
But the senior chief inspector of schools repeated his previous assurance in September that Standard grade would not be sacrificed as an external exam "for the foreseeable future" and until the Higher Still changes had bedded down.
The inspectors echo a favourite theme of Mr Osler's that there may be a case for specialist teaching in areas such as science and technology in the upper primary.
The report also suggests that its proposals for a more coherent and limited curriculum in S1 and S2 are at odds with the subject-based and promoted post structure of secondary schools.
Platform, page 16.
Comment, page 17.