The other problem is the campaign itself I'm guessing. The units are probably placed in the mission editor as novice or even veteran. The units act a lot better with elite VeterncyLevel.
Here is a mission you can use to test the DD AI yourselves.
http://www.subsim.com/radioroom/down...o=file&id=1738
Single player can add it via JSGME.
You can stick you scopes up, see how long it takes to see you.
Fire up your electrics and watch how the DD's react.
You can try to out run them and see how much damage your going to take.
Its fun to watch them in time compression you get a real feel for what they are doing and how they react to you.