Battlecruisers and fast battleships cannot be distinguished by maximum belt thickness alone. Quoting equal belt thickness can conceal how much of each hull the belt actually covers. The subdivision protected behind that belt also changes the ship's ability to absorb damage. A single maximum-armour figure cannot describe the weight or effectiveness of the whole protection scheme.
Notable Point · 34:29-34:53
Armour distribution matters more than one belt-thickness figure
Equal maximum belt thickness does not settle whether a ship is a battlecruiser or fast battleship; coverage and subdivision reveal the fuller protection scheme.