Which is NOT one of the six rules of Restricted speed and extreme caution?

The principle of not accelerating when going downhill is key to maintaining safety while operating a train. Under the rules of restricted speed and extreme caution, the emphasis is on control and the ability to react appropriately to any potential hazards. Accelerating downhill can lead to a loss of control over the train's speed, making it difficult to stop in time if an obstruction or danger arises.

In contrast, the other rules focus on maintaining a low speed and being prepared to react quickly to any obstacles. For example, maintaining a speed of 10 MPH or less ensures that the operator has ample time to assess the situation ahead and respond appropriately. Stopping 2 cars from any visible obstruction provides a safety buffer, preventing potential collisions. Being ready to make a fast stop reflects the necessity of being prepared for immediate reaction in an emergency.

By adhering to all these guidelines except for unnecessary acceleration, train operators ensure the safety of themselves, their passengers, and anyone else who may be on the tracks.