It was me that said
I remember thinking if there are really people flying around who could only manage to get 70% on that exam then I hope they keep well out of my way
and I'm pretty sure I still think that way. (Within reason. All the nonsense about bureaucratic structures in the current air law exam seems to be rather less directly related to the safety of other users of the sky.)
I'm sure it'll depend on how you try to learn it. I had the benefit of evening classes as well as the self-study material, and personally I often learn better when someone explains to me how to understand something than if I just try to memorise a text book (at which I am totally cr@p). Also some of it depends on when you try to take the exams in relation to where you are with the flying; trying to understand the theory about drag and angle of attack and stuff seemed lots easier to me once I'd tried stalling an aircraft.