[averyrm]

1. Many operators taxi on one engine to save gas, the engine would have been turning during the flight no matter if it was on or not. The relative wind would turn the blades.
2. Many operators taxi on one engine to save gas
3. Probly route of flight
4. Probably just your perception/ acustics in the cabin
5. Don't see how that has to do one-engine flight.

The flight was conducted with both engines operating.