I have discussed this very concept with certification authorities for future consideration. Considering the many twin engine airplanes will not allow the autofeather system to feather the second engine, the same theme has merit when it comes to shutting down the engine entirely! There have been cases where two (both) engines were shut down by mistake, resulting in a crash. Automated systems, along with electric, rather than completely manual, shut off controls, gives us a new design opportunity to prevent what might be thought of as a single point failure in pilot action.