DTT shot is one of the more difficult(esp in TMO) but fun shots to accomplish.In stock I remember they would just run right at you in straight line, fire from 600 yards or so, pretty much assured youll hit an done torp took them down.Unfortunately TMO DD's have super bows for some reason so fire two fish usually and they usually do the trick.Although firing shot when they start zigging while coming at you instead of strait line can prove difficult at times but doable.
My favorite was I basically encountered what Wahoo did in Wewak Harbor in Jan 1943 which was the first successful DTT shot by US subs....lone DD patrol, I infiltrated submerged, fired at the DD and missed, it came at me, didnt zig like most in TMO did, fired when DD was at 550 yards and closing, then headed the short distance to bottom.BOOM i heard(external view disabled) came back to surface and raised scope, DD was on fire and sinking
Note:I placed a lone Shiratsu DD in Weawak Harbor via the ME, in case i ever wanted to try this in campaign when i was in the area.