TIL that the Italian's Pugliese torpedo defense system was actually not that bad. The flooding issue that comes up when criticizing this system is due to it's own passive counter flooding mechanism. Pugliese incorporated several channels that ran through the triple bottom of the Littorio's that, when one side is struck and flooded, would transfer water towards the other side automatically, meaning the ship would roll less and would (hopefully) require less attention from the crew and could continue fighting. Counter flooding was normally done on all battleships after torpedo damage, to balance out the weight of the water in those compartments. Where the Pugliese (and all torpedo defense of that time) had problems is that torpedoes with magnetic fuses that ran just below the ship could do significant damage, as seen in Taranto 1940.
further reading here: The Littorio Class - Google Books