Im at the Kagero now, and let me tell you this:
If i fire torps from a distance longer than lets say 10km, hitting my target is extremly unlikely. In the time the torps traveled there, my target changed course way too often. Even if his change of course or speed is minimal, my "torp wall" of 8 torps will not hit. Since my torps travel 20km, i get the odd torp hit now and then, but not at a target i aimed for. Even with my 20km of range, i need to get as close to my target as possible ~about 6-7 km, which is dangerously close to getting spotted. Then i have a high chance to get atleast 1 hit. The only times i hit with more than 5 torps is either completly random lucky coincidence, or like people say, the target didnt change course for atleast 1 minute (which is a loooong time),
The trick is, you cant just be always at 6-7 km close to your target, because you get spotted by other dd's, planes, or sudden course changes of your targets, which more often than not end fatal, because kagero isnt exactly fast.
I think the best way for you to understand this, is when you played dd's and have a change of perspective.
