The problem with Prof Beer's tests wasn't even so much that they were difficult, unpredictable, and often vaguely worded, but that the number of mistakes in the question statements and his later refusal to admit said errors rendered the tests impossible to complete. I don't believe that he managed to write a single exam in either semester that didn't have at least one major error in it that was caught either during the test (after most students had expended a lot of time fruitlessly struggling to solve it) or afterwards, when the TA went over the exam in recitation.
Perhaps it would have helped if prof beer actually came up with an answer key instead of handing off that task to the TA after the test had been administered or even if he had just, you know, read over the exam once before giving it.
The worst example came up during one of the later exams of the second session when he provided a table of data which did not include the necessary information to solve the problem because he'd copied the wrong stuff. When this was brought to his attention after the TA and class discovered it while going over the test solutions during recitation, did Beer throw the question out or give the points to everyone free? No and no. He had the TA grade the question according to "how much it looked like the student would have been able to answer it had the table been correct." What the hell is that? I felt bad for the TA.