We all seem to be better shots than most real submarine commanders. i think the game is missing a few "complicating factors"... So don't take it too seriously.
Wasn't it a British sub commander who said the angle off is always about 10 degrees? Let me see... a 40 knot torpedo at a 7 knot target at 90 degrees AOB - well waddayaknow? Saves a lot of messing about, especially if you have an eight torpedo salvo. Plus it means you get to go home much sooner.
I've actually used this to fire using a hydrophone bearing on a target I couldn't see at all. Sure enough, a hit!