Why 10-inch and 8-inch cruiser bands fail

What if the London Naval Treaty defined 10-inch heavy cruisers and 8-inch light cruisers while retaining 16-inch battleships?

The categories would yield poor cruiser designs and could collapse the treaty by narrowing the practical separation between cruisers and battleships.

The 10-inch gun is rejected as an unsatisfactory compromise: its rate of fire is compared with a 12-inch weapon, without enough penetration advantage over 8- or 9.2-inch guns. German interest in 11-inch guns is linked instead to the velocity they expected to obtain. An 8-inch light cruiser would also lose the volume-of-fire advantage of 6-inch batteries at likely engagement ranges. British and American studies are cited for the greater shell output and chance of hitting with 6-inch guns. Moving heavy cruisers to 12-inch guns would then make a reduction to 14-inch battleship guns harder to sustain and could encourage 18-inch battleships. The proposed categories would weaken the separation between cruisers and battleships and create further pressure on the treaty system.