Mud, that's a very good point. There IS a difference between fear and common sense. For example, I live in an area where there are a lot of rattlesnakes. I have an animal science degree, and know their behavior, therefore I do not fear them. However, I am well aware that a rattlesnake bite can be fatal, therefore, my knowledge of their behavior (and common sense) keeps me from doing something stupid that would result in a bite. Even without fear, common sense tells you what can harm you, and common sense tells to how to act appropriately in dangerous situations.
I guess the question in the case of this woman, is does she lack fear of pain and injury, or does she lack fear of dying. Common sense says that having your throat slit can cause death. If she does not fear death, then it makes sense. Otherwise, yes, it seems to be a lack of common sense.
