Thanks for the great info. rudewarrior ! Yes, I was thinking more in terms of u-boat safety; as you know I'm sure, one of the main reasons they quit stopping, etc. ships was because of the ships firing on them, signaling their location, etc., all of which the ships started doing fairly early on.
I'm surprised it's even mentioned in the handbook, at that stage of the war.
Maybe like most handbooks, there was the book way and there was the real life way.
