the only time i have sunk destroyers is in multiplayer usually when we have agreed to keep the homing torpedos reserved for the DDs especially when we have unlimitted torpedos and then only if the DD is attacking another player.
My tactic is wait for the DD to be clear of other ships and point and shoot the homer it will hit eventually .
Sank a whole load of escorting destroyers juast by this tactic before attacking the convoy. This was in GWX2 aswell.
