Why WATU used repeated war games

WATU was established in January 1942 once sufficient information existed to begin systematic tactical experimentation. Its founders wanted a director who understood both anti-submarine warfare and the Royal Navy's existing wargaming tradition. Gilbert Roberts brought experience designing games at the Portsmouth Tactical School to develop new strategies and tactics. Repetition mattered because a single successful game could be an outlier rather than evidence of a sound method. Credible results could therefore require a scenario to be run one or two hundred more times over days, weeks, or months.