What should motormen operating from cars other than the leading car avoid doing with the controller?

Motormen operating from cars other than the leading car should avoid advancing beyond a set limit with the controller due to safety concerns. This practice ensures that trains maintain safe operational parameters and do not exceed designated speed limits or interfere with safe stopping distances. By doing so, potential risks of accidents or damage to the train and infrastructure are minimized.

Operating from non-leading cars can introduce complexities in communication and control, making it crucial for motormen to maintain strict adherence to these limits. If the controller is advanced too far, it could lead to unintended acceleration, which could be particularly hazardous if the train is approaching a station, signal, or any other constrained area. Safety protocols are designed to mitigate these risks and promote safe operation throughout the train system.

Other options, while important in their own right, focus on different operational challenges that may arise but do not directly highlight the critical nature of adhering to operational limits as the correct choice does.