This "major academic study" reveals how slipshod notions of language have become. Colloquial language is appropriate for speech rather than writing: the "dramatic increase" of this in written exams shows a lapse in standards, as candidates are now unable to distinguish between the two kinds of language and the examiners do not, apparently, consider the distinction worth preserving.
We read that "otherwise able 16-year-olds often wrote at length without any full-stops or commas": that "otherwise able" is good! What this reveals is their inability to realise the breaks and divisions in their thinking: so, how could their ability be judged high? It is absurd to regard punctuation as a disposable convention, unrelated to the underlying organisation of thought. It is not, therefore, surprising to read that even A-grade pupils could not distinguish "of" from "off", because of the laxity of this "examination" system.
"Findings on spelling were less positive" - in other words they couldn't spell as well as their predecessors of 10 or 20 years previously; the phrase "less positive" is Orwellian in its aim of concealing an unpalatable truth.
Language has been corrupted in the so-called educated class whose business it is to uphold standards.
"Pupils have better mastery of written English" - emphatically not, as the report demonstrates.
Nigel Probert 15B South Snowdon Wharf Porthmadog