Highly qualified instructors were an essential element of TOPGUN's success. Mediocre instructors are unable to hold the attention of talented students. TOPGUN instructors were knowledgeable fighter tacticians assigned to one or more specific fields of expertise, such as a particular weapon, threat, or tactic. Every instructor was required to become an expert in effective training techniques. All lectures were given without notes after being screened by a notorious "murder board" of evaluators who would point out ambiguities or flawed concepts in the draft presentation. The curriculum was in a constant state of flux based upon class critiques and integration of developing tactics to use new systems to combat emerging threats. Instructors often spent their first year on the staff learning to be an effective part of the training environment.