What action would violate the rules for a train operator?

Coasting with the reverser centered would violate the rules for a train operator due to safety concerns and operational protocols. The reverser is a critical control that determines the direction of the train. When it is centered, the train is in a neutral position, which can lead to a lack of control. This can be particularly dangerous if coasting occurs at high speeds or in areas where precise stopping is necessary, such as near stations or switches. Train operators must maintain full control of the train at all times to ensure the safety of passengers and the integrity of the operation. Proper use of controls, including the reverser, is fundamental to adhering to safe operating practices, making this action a clear violation of train operation rules.