This is not to suggest a dichotomy between the two. Theory does not exist qua floating abstraction, without reference or basis in reality. As such it is a reflection on the nature of existence, the nature of man, and the relationship between the two. Practice, or action, is human action. Political-Economic theory is the body of fundamental principles underlying the science of human action.
Theory is abstraction.
If a theory is correctly formulated, it is eminently practical. Ideas are not separate and apart from those who think them. Actions are not distinct and apart from those who act them out. Actions are necessarily - implementations of ideas.