What Japan gains by designing treaty ships around stability

What could Japan do with resources saved by avoiding topweight problems and later ship reconstructions?

The result depends on whether Japan still falsifies treaty displacement: honest designs lose some desired capabilities, while continued deception permits more ambitious but risky ships.

Designing within stable limits would prevent some expensive corrective work, but it would also force the navy to admit tradeoffs among weapons, protection, and displacement. Honest treaty figures would restrict the capabilities Japan tried to place on each nominal 10,000-ton hull. Continued deception would instead leave room for genuinely larger ships, perhaps with still more ambitious turret arrangements. The counterfactual therefore changes outcomes only if it also changes the institutional pressure to conceal displacement and overload the design.