If it drops to 58hz or lower in 60hz countries u have chances of blackout. If the hz falls too low it just means the power station is overloaded. And whatever it is using to make that electricity isn't spinning the alternator at its correct speed.
That engine cleaned up quick, after it got up to governed speed. Was it already warmed up, or was that a "cold start"? (good fuel atomization, high compression)
