Benchmark navies could shape rivals through selective performance figures

A digression from sailing ships explains how the Royal Navy could report speeds achieved under normal peacetime regulations rather than the harsher machinery use accepted in war. Because other services compared their designs against the benchmark navy, precise definitions could influence foreign expectations without publishing a false number. The age of sail posed the opposite problem: hull and sailing performance were harder to hide, but closed gun ports concealed a vessel's actual armament. The same outline might hide two fully armed decks, a lower deck cleared for troops and supplies, a lightly armed fluyt, or an East Indiaman rather than a fourth rate. The discussion uses a rule of thumb that one year of wartime machinery use could equal six years of peacetime use, explaining why a truthful normal-service speed might understate what a ship would attempt in combat.