The Craig-Martinez method is a popular free-interface component mode synthesis method that allows for building reduced models from large finite element meshes. These reduced models contain both physical and modal degrees of freedom. As far as the authors know, the usual description of the Craig-Martinez method uses a pseudostatic approximation which may be stated as follows: the highest excitation frequency of the structure can be neglected in comparison with any eigenfrequency of the free vibration modes eliminated from the reduction basis. This short note aims at introducing the Craig-Martinez method in an original manner by reformulating the usual pseudo-static approximation into a simpler statement: the initially truncated high frequency free vibration modes do not dynamically participate to the reduced-order model.