Crossing the T with shells that failed the fleet

Jellicoe used incomplete information to deploy across the German line of advance and cross the High Seas Fleet's T twice. The maneuver depended on his judgment and on years spent turning the Grand Fleet into an instrument that could execute a complicated deployment on time. British armor-piercing shells often failed to penetrate and detonate as intended, allowing heavily damaged German ships to survive hits that might otherwise have been fatal. The battlecruisers suffered losses, while none of the battleships Jellicoe had trained most directly were lost. The Third Battle Cruiser Squadron had been sent north partly to improve its gunnery.