Why learn theory?
Theory provides a strong structure and explanatory framework to support a graphical concept or idea. It gives an idea more depth and meaning and therefore more structure to support this concept. It can be used to explore support and develop as well as being a base for critique.
As a designer it is important to develop a visual 'voice' and authorship to work we create. We craft our own style and approach to a graphical problem and this is what makes our work unique. In the commercial world this is especially crucial.
Once we apply logic to our work it enhances and expands creative freedom by grounding us.