When I have a DD in my vicinity and I "want it" or have to deal with it, I set my torpedoes, go silent running, if possible, stop engines, and have given bow shots successfully.
But if I'm dealing with a convoy, I avoid the Escorts as much as possible. I always have a stern torpedo set for taking them out.
Just love it when they get surprised with a bow shot (just like in the movies Run Silent and Run Deep when they went to the Bungo Strait)
Rob