How longer gunnery ranges changed Invincible's protection logic

When HMS Invincible was designed, her expected engagement range made speed a form of protection: she could move faster than an opponent's guns could track her. Better observation and targeting extended expected engagement distances by 1914. At those longer ranges, a small change in a gun's angle covered much more distance at the target, so Invincible's speed could no longer defeat traverse in the same way. This changed the conditions behind the original design rather than simply exposing foolish designers. As a result, the battlecruiser moved toward heavier protection while the battleship sought more speed, with both lines converging on the fast battleship.