I know this is not fundamental solution but a way to work around this is not use TC faster than say, 256... means needs to change the mind in playing tho...
With 1024x compression you get unintended "cheat" as the game slows down to calc the encountering ship, means you know there's a ship near without no report etc.
When I started playing vanilla SH3 as it was just released, I spent most my time in the map view and 1 patrol took about 5 - 8 real world hours. 2 years later now I installed those "realism" mods and less and less time compression... learned to "save" games

and I'm not sure how long 1 patrol takes now... maybe a few weeks or months.. Because it's like this...
I'm now chasing a convoy in 15m wind storm. The weather has been bad for 2 days now. I'm playing with almost 100% difficulty with NYGM mod so I never know how far the convoy is ahead of me. I will not be able to attack this convoy from behind obviously, so I will have to be ahead of convoy when I attack. But of course I can't do the dash now because if I do I'd probably be not able to track the convoy. The weather is very bad and I can't have any visual contact (it's 200m - 300m visibility in typical SH3 15m storm). And with the mod, the damn convoy
changes the speed and course!
So, what I have been doing is, every 30 minutes or even in 15 minutes I submerge and check the course of the convoy and guess the speed (rough idea in relation to sound level of convoy). Mark on the map. Mark, mark, mark. 15 min is a short period of time for using TC so I run SH3 while I am
working on my real job on the second laptop computer

, listening hydro guy's report.
I don't know how long this bad weather continues but I have to continue this chase (15-30 min dive check) just not to lose the convoy. I guess I'm near to the convoy as close as 6 km now. When the weather gets better, there will be a great chance of the escorts can spot us immediately -- this alone makes me using TC as less as possible. Then when I get visual, I need to set up "attack course" at ahead flank.
So if I play like this, I spend an hour or two (of real time) JUST to chase the convoy and no shooting

But it's maybe kinda "realistic" isn't it

I'm not sure if I can "get" the convoy as I wish in... and when? eh, next week? lol
Anyway, this is
one way of enjoying game - after lots of lots of shootin 'n kaboom excitement
Ah, yeah, I'm getting older, lol :rotfl: