[Ithekro]

The Germans had designed the barbettes of their twin 15" gun turrets the same size as their triple 11" gun turret so they could swap out the triple turrets of their battlecruisers with twin 15" turrets once the new guns were built in enough numbers. (The Japanese did something similar with the Mogami-class cruisers. Built them with 155mm guns in triples but swappeed them for 200 mm twins after they left the treaties behind.) The war started about six years before the German Navy might have been somewhat viable as a surface fleet.

Bismarck's successor class, the H-39, was to have twin 16" cannon turrets and still more or less have the silouette of their heavy cruisers and Bismarck.