The Dido comparison exposes a cruiser-on-cruiser mismatch

The British Dido-class cruiser gave up roughly nine knots but possessed the protection needed to remain in a gunfight. Its belt, deck, magazines, and bulkheads were armoured, even though its 133 mm main guns were close in calibre to the Italian ship's 135 mm weapons. Dido carried fewer torpedo tubes and could not dictate range through speed as easily, but it was built to survive the kind of exchange its cruiser label invited. The Capitani Romani could escape many such encounters only while their machinery and tactical situation remained favourable. The contrast shows why classification was operationally dangerous: it encouraged comparison with ships designed to absorb damage that the Italian hull could not.