An academic discourse is chemistry. If you identify yourself as a chemist, I think you should be able to explain formulas, theories, experiments, and the periodic table. I am in no way literate for this academic discourse community. I could not tell you half of the things on a Table of Elements or how to conduct and experiment using chemicals and formulas. Being literate in this field means knowing the basic foundation of chemistry as well as obtaining more in depth knowledge about the subject. For example, a chemist would explain things differently to me than he would his lab partner. This consensual language between the chemists allows them to further advance in the field without worrying about having to make sure the other person knows what you are talking about. It is kind of like having to take a pre-requisite before you are allowed to take the class you want. Authority has to make sure that you are proficient and can function in that academic discourse community.