Thanks everyone for the great responses. It is very impressive to see such a lively forum for an old game!
You have given me some good things to think about, and I'm going to stop trying to be so damned efficient, and just flow with the stream of gameplay. I just put out to sea again tonight, and this method is working well, along with using the real time more often. I can now see that using time compression too much and you miss the forest for the trees.
Mittelwaechter: That is very impressive. I've listened to the hydrophone before (I love my Sennheiser cans!), and have spotted things my Sonar man missed... but I can't begin to imagine "flying blind". How interesting.
I'll put some sub books on my reading list. Interesting about the survival goal, particularly that 1943 is so elusive. Now I have a goal.
Yet -- with save games -- why would it be hard to eventually get there? Do you not go one with a game if you die?