Binary logic diagrams ({BLDs}) are widely used to document the functionality of logic-based control systems. The ambiguous functionality implied by certain {BLDs} is highlighted by drawing analogies with asynchronous sequential logic systems. Non-deterministic state transitions in these {BLDs} occur due to the existence of hazard and race conditions or, equivalently, non-unique feedback cut sets. The need for additional specifications to remove this ambiguity is discussed, and recommendations are made to aid in the specification of {BLDs} with unique functionality.