Well from what I’ve seen so far Maths is the major stumbling block for ALOT of people in these courses. While a C3 in Ordinary Level Maths is the minimum requirement in most of the courses, we went into first year and had Maths as a year long module which was basically the Honours Maths course with a few bells and whistles in the form of some “simple” Applied Maths. Not something someone coming from the Ord. level wants to see, especially on top of all the other course work.
And I’d agree with the comment that the LC isnt a good indication of ones intelligence. To me its more an exercise in memory, however when something unexpected comes up its always good to be able to fallback on your actual understanding of the subject.