What is the main reason for not using a cheater bar or extension tool to fully close the handle on a load binder?

Using a cheater bar or extension tool to fully close the handle on a load binder is not advisable primarily because it can place too much pressure on the load and/or tie-down points. This excessive pressure can compromise the integrity of the load and the securement points, potentially leading to overloading or damaging the equipment and materials being secured. A load binder is designed to apply a specific amount of tension for safe and effective securing of loads, and using a tool to exert more force can exceed that design limit.

Additionally, while other options may contain elements of truth, they do not directly address the primary concern related to safety and load integrity. Option A regarding the potential to break the handle may happen if excessive force is applied, but it's more about the overall impact on the load itself. Option C discusses uneven load distribution, which could also be a consequence of over-tightening, but it stems from the pressure issue rather than being the main reason. Option D about standard operating procedures can be important, but ensuring proper load safety and pressure is a fundamental operational guideline represented in those procedures. Thus, the crux of the matter lies in the risks associated with misusing tools to exceed the intended force on a load binder.