The true strength of the Type 93 was its speed, not its range. Even the 15% figure the IJN believed to be reasonable is, at best, fantastical and at wo
rst utterly divorced from reality.
Even in short range engagements, the best achieved with any significant number of torpedos launched was 13.5% (I exclude Ormoc bay because four torpedos were launched, of which one hit), for an overall accuracy in the scenarios the IJN envisioned a 15% hit rate of
6.71%. (That is to say, less than
half of the accuracy the IJN believed they would achieve)
This is not to minimize the power and danger of the weapon, but rather to put it into proper perspective. It is only with short-range salvos that the IJN was able to properly leverage the strengths of their weapon.