Tech Question

[Kaiser Kirk]

While looking at Rocky's cruisers, I went to reference a rule and found I've been understanding it wrong

Cruiser Architecture:
Baseline: guns in single mounts or casemates, on side/centerline
1900: ammunition hoists, deck torpedo armament, superfiring mounts. Cruisers under 6000 tons may have cross-sectional hull strength > 0.9
1910: twin gun mounts (require hoists); powered gun mounts; unrestricted weapon armor
1920:  No restriction (high or low) on caliber of turreted guns. Cruisers under 3000 tons may have cross-sectional hull strength > 0.75

I've been shooting for an Overall of 0.9  not a cross-sectional of 0.9.

Looking at Snip's Lauri and Iaculum, both have cross-sectionals under 0.9, but overalls at 0.9.

So I think it's a typo to be corrected.