Springsharp and survivability

I have not tried to look closely at how Springsharp determines how survivable a ship is. I like the fact that relatively lightly armoured ships have what I would consider to be good survivability ratings. A ship with better protection, such as the fast battleship version of the Super Lion concept has very good survivability. I guess that the more lightly protected ships still show a good resistence to torpedo attack, even if the number of large caliber hits is not that large. Even the Super Lion fast battleship will only take 32.9 15in hits, but will resist up to 7.6 torpedoes. I guess that 8 torpedoes would sink the ship, while it might survive 7 hits, just barely. The GB/CA/1921d design will still resist 4.3 torpedoes, and 77.8 1oin hits. The GB/CA/1921d design only has a 5in belt, but does have a 3in deck, as does the Super Lion fast battleship. They both do have a 2in torpedo bulkhead, so that they are relatively well-protected by 1905 to 1921 standards. By 1939, typical practice for large armoured ships was to have much thicker torpedo bulkheads.