I had a college physics professor who was literally this bad... she taught all of the fun physics experiments in class, and then tested us on mathematical aspects of physics that were never covered in class. over 75% of the people who took her class failed, and that includes a huge curve (anything over a 60% on her tests was an "A"). When I asked another noted physics professor there why nobody has questioned that rate of failure in her classes, he replied, "Are you kidding? She's a woman, she's a minority (asian), and she's tenured... the only thing she's missing is a limp. Nobody is calling her out for anything."