Kongo reconstructions and HMS Tiger test the boundary

Reconstruction can move individual ships toward a new category without necessarily reclassifying their entire class. In the classification used here, two Kongos may have crossed toward fast-battleship status because their yards added enough subdivision and armour coverage, while the other two did not. Drach's classification keeps all four on the battlecruiser side of the line. HMS Tiger was already unusually close to the boundary for a British battlecruiser of its generation. Denser subdivision and broader armour would move Tiger quickly toward fast-battleship qualities, but the resulting cost and weight reveal why the distinction mattered to designers.