The first 13.5-inch ships were marketed as super-dreadnoughts, making their guns a status symbol as well as a combat advantage. An Australian flagship with that battery would carry more prestige than a 12-inch ship. The production question depends on when the Dominion orders entered the program: the Orion battleships, Lion, and Princess Royal were already ordered. Choosing 13.5-inch Dominion ships would increase the relevant group under construction from six ships to eight. The available industrial base is judged capable of absorbing those two additions.
Notable Point · 18:36-20:18
13.5-inch guns as a status purchase and an industrial commitment
The 13.5-inch battery offered greater contemporary prestige, and two Dominion orders could join an established production program.