Similarly, with a slight twist, a prof I had used to recommend we read the entire text book, not just the chapters required for the class. It was an open book exam so people figured they could annotate the pages or whatever and didn't bother to follow his adcice. He would often say, 'everything [we] ever want to know is in that book!'

He was right. The final exam was verbatim the practice exam given at the end of the book. As luck would have it, I had discovered the practice exams a week earlier. Once I realized they were identical to the final, I literally copied the answers and handed it in. It was a 3 hour exam and half the class was done in 15 minutes.