Which method involves testing what the system does if all operators let go at once?

The Whistle Test method is designed to assess the reaction of a rope rescue system when all operators release their hold at the same time. This test is crucial in understanding how a system behaves under extreme conditions, essentially simulating a scenario where all personnel involved in a rescue operation suddenly cease their engagement. The "whistle" serves as a signal, indicating when operators should release. By observing the system’s response, rescuers can identify potential vulnerabilities, ensure safety protocols are adequate, and verify that the equipment will perform reliably even under sudden changes in loading conditions.

This method emphasizes safety and preparedness, aiming to build confidence in the equipment and the overall rescue plan. It provides insights into the needed safety margins and the effectiveness of the rescue system, ensuring that operations can be conducted with awareness of potential failure points. The other options relate to analytical methods or testing but do not specifically focus on the collective release of operators, which is the key aspect of the Whistle Test.