Back for good. Having been both an employer, involved with graduate recruitment, and now back at uni and involved (but thank god, not responsible for ) admissions then what you want is to be able to compare candidates, whatever year they sat the exams. In both roles I had/ have to consider applications from students who sat these exams at different times and be able to compare. It would be ridiculous to expect unis, let alone employers, to somehow weight results according to what year they were taken. Currently exam marking is criterian based, so in theory, you have an absolute objective judgement based on how that candidate performed against a mark scheme, rather than a relative one. I think my O levels did have a relative mark scheme but then it mattered diddly squat whether I got a 1, 3 or 5 and I got into a RG uni to read History based on my 5 O levels, 2 1s, a 4 in English, and 2 5s, with a retake in French and BBD at A level (more than happy to concede they were crap results but I did get to queae overnight to see Led Zeppelin, not to mention seeing Bowie as Ziggy Sardust and still met my BC offer!!!!) and I got a 2.1, which obviously would now be a 1st because of grade inflation (really? when none of us ever left the bar early, and you could still get away with getting your head down a month ahead of finals and suddenly realise how fascinating your subject was, I am finally indulging that interest now!!)Results then just didn't need to discriminate so much that these fine differences between cohorts and exams sat, actually mattered
The reality that anyone involved in the teaching profession at whatever level appreciates is that students work harder and teachers are getting much better at teaching them to pass exams and that has led to results inflating year on year. That is not to say that the current system is fit for purpose, clearly not if the students are emerging without the skills and abilties unis and employers want to see and unis are struggling to identify the brightest pupils. I certainly haven't enjoyed seeing my daughters "education" sacrificed once they reach Year 10 to them being trained like racehorses to pass the A* winning post ( and having to be the one that still inspires them to love and understand their chosen subjects in their widest sense ). However you don't address that by moving the goalposts in the existing system so noone knows whether a A one year is a B the next or worst of all that candidate who appears not to have a GCSE English would have had last year, or vice versa.
As a historian it is quite clear to me that Gove will be judged by posterity as one of those "conservatives" (v. small c) that tried to impose his own perception of an idealised past on others.