Scheme Z relied on uncertain morale effects

Pound ranks actually destroying submarines above the psychological effects of hunting them. Scheme Z is unlikely to achieve many kills, although a lucky encounter could succeed. He proposes dropping depth charges during a search even before contact, maintaining a hunt while contact lasts, and observing submarine movements from the air. His expectations about morale depend on assumptions that submarine captains would be capable volunteers while their crews would have less reliable discipline. Because those effects are uncertain, he considers the scheme too dependent on luck. He nevertheless states that he will conduct the operation if the Admiralty adopts it.