This article proposes an application of a derisking methodology of subsynchronous torsional oscillations considering a realistic use case. The main objective is to summarize and draft a synthetic paper clarifying the complete methodology highlighting the main information needed step-by-step. For exemplification, a real model from a decommissioned oil power plant is adopted, where a fictitious high voltage direct current power link is connected. In this article, stress is laid on details of the application of the derisking methods: the unit interaction factor and the complex torque coefficients method. Then, the different steps to obtain results are explicitly explained. Moreover, the design and tuning process of supplementary subsynchronous damping controller is discussed. This mitigation section uses minimal information to correctly damp the unstable oscillations, as one would expect from industrial projects where the data sharing may be limited. Finally, the resources needed to perform each step of the study were summarized.