A separate battlecruiser category at Washington

What would a separate battlecruiser limit on top of the Washington treaty's battleship allowance change?

It would likely be a five-ship category, preserving more fast capital ships while making national tonnage and carrier-conversion bargains much harder.

A separate battlecruiser limit would likely be five ships because the Washington ratios were negotiated in fifths. Britain would count Hood and Tiger, retain room for additional construction, and still need to fit the ships within a tonnage ceiling. Japan might keep all four Kongos only if their combined displacement fit its smaller allocation. The United States could retain five Lexingtons, but that choice would complicate the separate carrier-conversion settlement. A new category would change the bargaining links among battlecruisers, battleships, and carriers as well as the permitted hull totals.