Duke of Edinburgh as a late armoured-cruiser benchmark

The Duke of Edinburgh class carries six 9.2-inch guns in single turrets and ten 6-inch guns. The Warrior class keeps the six 9.2-inch weapons but replaces the secondary battery with four 7.5-inch guns, giving it something closer to a pre-dreadnought battleship's mixed-calibre arrangement. Minotaur goes further, pairing four 9.2-inch guns in two twin turrets with ten single 7.5-inch guns. Despite carrying fewer 9.2-inch guns overall, Minotaur can fire four on a broadside, matching Duke of Edinburgh and Warrior. The criticism of the later classes concerns the increasingly heavy secondary battery, which narrows the distinction between the two gun calibres' jobs. By that definition, Duke of Edinburgh is the last of these designs with a convincing separation between primary and secondary armament.