Inelastic structural models used for performance-based design intrinsically dissipate a part of the total amount of the seismic energy imparted to the structure. To take into account the energy dissipation sources not considered in the structural model but that nevertheless exist, damping generally is added. Given an inelastic structural model, state-of-the-practice documents thus advocate to add a portion of damping that is consistent with the inelastic structural model used. The main purpose of this contribution is to investigate whether it is a priori straightforward for practitioners to consistently add damping or not. There is indeed no clear theoretical framework for adding damping. This investigation is based on a reinforced concrete moment-resisting frame tested on the shaking table of the École Polytechnique of Montreal. Numerical analyses were carried out with ten different combinations of inelastic structural models and added viscous damping models. The main conclusion of this investigation is that it is a complex task to add viscous damping in a way that is consistent with the capacity of the inelastic structural model to dissipate imparted seismic energy. In the context of RC moment-resisting frame structures in seismic loading, without considering any interaction with the surrounding environment, computing energy dissipation quantities can serve as an indicator for assessing the consistency looked for and appears as a paradigm for performance-based engineering.