This is especially true in classes which are more heavily geared toward statutory law, such as tax law (which in the USA is governed by the Internal Revenue Code) and certain areas of commercial law (particularly courses dealing with the Uniform Commercial Code).
The statement emphasizes that classes focusing heavily on statutory law, like tax law (governed by the Internal Revenue Code in the USA) and specific areas of commercial law, especially those based on the Uniform Commercial Code, are more likely to be relevant to this concept.