Great read; however, I feel Prof. MacKay misses an important point. Employers fuel the problem, demanding this-and-that. People are going to university to meet the criteria for an top paying job, rather than passion for the subject. This is what is causing the grade struggle: student rush, cram, and rote memorise to achieve desired grades; most don't give a damn about interacting with the material. If you said here's an 'A' they'd take it, and not care about not knowing the material.
First, we need to restore university as an institution of learning [instead of a qualification mill]. In fact, I might be inclined to argue that grades should be abolished outright - almost what Prof. MacKay is saying.
[disclaimer: I'm a student at a world renowned British university]