It is tempting to picture a training system as a machine whose output follows from its inputs: the syllabus, the simulator, the manuals, the cadet. On that picture the instructor is a component — necessary, but interchangeable.
In a competency-based system, the instructor is the decisive variable. Give two instructors the same syllabus, the same simulator, the same scenario and the same cadet, and they will not produce the same outcome, because almost everything that matters in Competency-Based Training and Assessment (CBTA) turns on instructor judgement.