How strong might Argencourt's underwater protection have been?
Short answerA substantial contemporary torpedo-defense system is plausible, represented conservatively by the middle rather than maximum protection option.
NotesThe design exercise selects the second of three available underwater-protection levels. That option reasonably represents contemporary state-of-the-art practice. Choosing less than the maximum keeps the reconstruction conservative and avoids importing later protection standards. The uncertainty is handled through an explicit, bounded assumption.