One of the most irritating things about all things Silent Hunter is the jack-rabbit ship starts. It's like if they have 8 boilers, all 8 are always on line, fires on full, and they can jump from 6 knots to 9 knots inside of 1000 meters... that is the next most common method people miss by. I have locked onto a target before and left the scope up, and watched them do this, so anything shot for the rear mast only stands a good chance of missing behind. In the same vein, they have brakes as good as Bugs Bunny has in Hair Brakes, and can stop short of a dime from 1200 meters, no matter their speed, so anything shot at the forward mast only, will miss forward. Very frustrating. If you shoot one at the forward mast, and one at the rear mast, they kind of seemingly don't know what to do, which is where you'll see them turn on that dime when stopping also, and the torpedoes "comb" them...
The DD class is the worst offender. My big question is "how do they see the electric torpedoes at 600m anyway?
phwew!
lurker (original OM author) did attempt to fix that with a lot of the ships, but it is still there, since it is a basic game AI function.