Plus ca change on comparability
"Meanwhile, the syllabus had grown to 12 pages in the regulations, including a booklist where there was none before. It seems to me quite likely that in 1968, with the dependence on one examining technique only, the exam failed to assess adequately what many candidates had learned, whereas now (in 1976), with the inclusion of more techniques, there is more opportunity for candidates to reveal what they know. Alternatively, one could argue that both exams were appropriate to their syllabuses but that the versions of chemistry learned and examined were not the same. Either way, comparability of grades between the two years means very little."
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