This might sound a bit thick but do the entrance grades for courses reflect the difficulty of the subject matter? Like, if the offer is high and you only just scrape it would that mean you would have problems with the difficulty of the course? Or are the entrance grades mostly reliant on demand for the course, more people want to do it so they need to push up the grades? Just curious.
Popularity plays the biggest part I think. I've applied for English and most universities that are considered good but aren't hugely renowned or anything want at least AAB. In contrast to that, when I've done searches on French courses for the same universities they mostly ask for BBB/BBC.
Mainly it is popularity of courses. My geogpraphy offer is AAB, but i'd applied for geology, which is at least the same level of difficulty, at the same uni, I'd only need BBC. Starting to wish I'd applied for geology now..!
My old headmaster reckons it's got to do with the popularity of the course and of the uni.