Re: Why do we have a set pass mark for grades?
Marking to the curve is a double edged sword, and I accept that it makes comparing marks year-on-year more difficult, but you have to ask what the point of the exams actually are?
When I was doing my 'A' levels in the late '70s, the primary reason was so that you could be selected for further education. As there were many fewer university places available, the marking was set so that you could tell who was 'the best' from that year's student population. If less that 10% of the students got an A, these people, who would be the most likely to excel in that subject, got streamed to the best Universities. The next tier down could select from the remainder, and on downward through the Polytechnic system, aiming at people who would excel at HND qualifications, but may not be up to a full degree.
It did not matter whether there was grade comparison between years, it would be accepted that the best people would always get better marks than the weaker candidates, so the streaming would still work, and the 'right' people would always get to the establishment that best suited them.
Quite often, it was not the grades that determined what type of work someone ended up in, it was how far they went in the education system. Students who had got to University and completed a degree course had demonstrated by that fact that they were worth employing.
It is only now that the 'A' levels that are intended to give an absolute measure of how someone's worth that this problem occurs. Since schools have been measured by result, and the curve has been discarded, it has completely devalued them as a mechanism for selecting the best students. Governments and schools each have an interest in 'improving' the results.
Part of the problem is also political. Educationalists in the '70s and '80s became convinced that non-competitive grading was the only way to avoid stigmatization of kids (abolition of the 11+ and Grammar schools is an example). Schools were not allowed to say to kids "look, you are never going to succeed in becoming a theoretical Physicist, best do some vocational training". All children are given unrealistic expectations by being told that they can achieve anything, and in order to persist this myth, the exams are set so that they think they are good at a subject, when in fact they could be only mediocre.
This is just dumb. Life is competitive, and that is never going to change. When you go for a job, the best candidate wins (unless the recruitment process is also dumbed down, but that is another rant!) And people not suited or without an aptitude for a particular job will never get it, regardless of how much they want it.
Setting kids up with realistic expectations, and giving them some taste of reaching their ceiling by allowing some of them to experience disappointment is a required life skill that they have to learn at some point, and my view is that it should be part of the school experience, instead of a post University kick in the teeth.