I read from the SUBSIM archives that the destroyer AI in SHII was a bit too good. I am in the middle of a generated mission right now and I wholeheartedly agree. I am playing an early war scenario and the destroyer busted out my XXI boat at All Stop on silent running. I lost him and have him leeward of the convoy, but I can only imagine who out of luck I would have been were I in a VII, IX or an Einbaum. Obviously, I have to treat the AI with greater care than the AI in III. Any advice from the Old Gang on how to avoid some of the nastier aspects?
EDIT: I did manage to sink the three ships clean despite the rabid AI.