Was Chatfield's preference for the 14-inch gun mainly about gaining more armour?
Short answerThe explanation offered is his background in Beatty's battlecruiser force and its emphasis on volume of fire; a heavier German opponent could still force the British armament upward.
NotesChatfield's preference for the 14-inch gun is connected to his experience in Beatty's battlecruiser force and its emphasis on putting a high volume of fire onto an opponent. In the Bayern counterfactual, the timing of Scharnhorst's construction would let Britain respond before laying down the King George V class. Twelve 14-inch guns are proposed as the minimum response to a six-gun 15-inch German ship. Nine German 15-inch guns would exert greater pressure, prompting speculation about twelve 15-inch or even 16-inch guns. Each remains a hypothetical British response. Germany could enlarge a working triple turret, while Britain could draw on its improved Nelson-type turret design.