I don't care what you have to say, sometimes, no matter how hard you study, and how much material you think you know, the prof will still dick you over on the exam, making it damn near impossible to do well (before the curve, that is). When the class average for an exam is in the 45% range, there's clearly something wrong with the way the prof is teaching the material, or what he is testing on is simply just not taught, period. I have had classes where no matter how far out of my way I went to look for material to study, be it text books, lecture notes, Google, etc. I could NOT do better than a 60% on an exam that semester. I still ended up with an A- in the class because the prof had to curve the grades so hard, but I just felt hopeless after every exam. A girl left our final in tears because it was so hard haha. In classes like that, I refuse to believe there was anything I could have done to do better on those exams, so I just had to rely on the curve.