Retaining the 5.25-inch gun for the Dido class remains plausible because a cruiser benefits from its heavier anti-surface punch. If 5.25-inch production were reserved for the Dido program, HMS Scylla and HMS Charybdis might receive that intended battery instead of the 4.5-inch upper-deck mounts they used historically. A more radical outcome has Henderson forcing the entire program onto the standardized 4.5-inch caliber. The lower mount weight could support five centerline between-deck twins plus four side-mounted upper-deck twins without the same topweight problem. Such a ship would be more lightly armed by cruiser standards but would gain extensive all-round dual-purpose fire and production commonality.
Notable Point · 33:10-35:40
An all-4.5-inch Dido could trade shell weight for gun density
If Henderson standardizes completely on 4.5-inch weapons, the Dido-class cruiser can use a dense mixed arrangement of between-deck and upper-deck mounts.