It really depends on the situation. People who make fun of a person who stutters by mimicking the stutter, or by saying things “can’t you just say it normally?” Is really offensive. Your professor is trying to get you to understand what goes on inside the head of a person who stutters. But that’s only a small part of it. The biggest part for me was the emotional effect it had on me. Anger, stress, anxiety, fear of speaking in public are all part of stuttering (or at least they used to be)