An analytical method for assessing the controllability of floating offshore wind turbines (FOWTs) is presented in this work. Modern linear control theory principles are applied to linearized FOWT models to establish quantifiable metrics to determine advantageous, or disadvantageous, differences in turbine models from a controls perspective. One use of such a metric is to consider the amount of work necessary to move a floating turbine back to an equilibrium point. We use a simplified point-mass model to demonstrate this idea. The idea is then translated to the DTU 10MW wind turbine on floating semi-submersible platforms. This work concludes with a discussion of the many potential uses for the quantifiable values associated with controllability within the wind turbine research space.