This paper discusses potential extreme scenarios which could result in unstable conditions on the main interconnected electricity transmission system of Oman. Case studies on loss-of-stability scenarios between different parts of the network are examined. The objectives of the study are to identify possible locations of the electrical centre of swing and to develop an approach for controllable system splitting. A controllable splitting approach has been proposed and sensitivity analysis has been utilised to identify potential locations for controllable system splitting. In the final recommendations, trade-off considerations should compare the introduction of a system-wide out-of-step protection framework and its associated potential complications versus alternatives (e.g. improved protection performance).