The optimal control theory has a sophisticated framework with powerful tools to solve practical problems in various fields of knowledge. However, this theory requires precise definition of the problems under consideration. In this respect, the correct weighting of the relative importance of the effects represented by aggregate elements to performance indexes is critical. The decision theory can help to overcome this mishap. In particular, the technique Analytic Hierarchy Process (AHP) is adequate for the task of consistently weigh the components of proposed performance indexes and has other advantages such as keeping a detailed record of the criteria, values, comparisons and judgments that guided decision making.