Surprisingly there seems to be little written on this. I checked my copy of S.E. Morison's "history of U.S. naval operations in WW2" which has 2 volumes on the battle of the atlantic. He has a whole chapter on ASW doctrines and problems, but never discusses this issue.
However, based on the various comments. I changed my copy to a 5 minute delay and tested it on the PQ-17 mission again.
Unfortunately, I wound up sneaking through the escort screen undetected:
...then torpedoed 2 freighters...
...then snuck away without getting detected...which I guess was not the point..
I will retest..
