You have been taught to blindly rely on the FMS inputs. Not a good thing. Where possible on SIDS and STARS and en-route too, it is wise to have a second or back-up view of your planned flight path by appropriate selection and monitoring of basic navigation aid readings. If installed in your aircraft, the RMI with its VOR and ADF needles and coupled with DME display, is an important situational awareness feature.
That is if you know how to use it quickly.