This paper's aim is to present an analysis of the influence of the 2-DoF controllers proportional set-point weight over the servo-control performance and to show that the removal of the existing constraint for its selection (0≤β≤1.0) will allow to improve its performance when a high robust regulatory control system is required. A concrete analysis is conducted by using 2-DoF PID tuning approaches that explicitly take the desired robustness level as a design parameter. It is seen that as the desired robustness increases the tuning methods suggest values β>1.0. Performance looses are evaluated if we are to be constrained to the case β≤1.0.