OK, TMO plotting fixes:
Friend/Neutral/Foe and merchie/warship colors are killed, both on ship position plots and sonar vectors. This is information that sonar, radar, and in most cases, visual sighting would not give you. TMO totally nerfs it with black for everything.
Target silhouettes are replaced with round position markers. Same as above, information not available to real observers. In the stock game you can even identify a radar target by its shape, a definite no-no if you're seeking realism. And you know the length of your target right on the plot. All that is TMI! Round target position indicators for everybody!
Target ID, course, speed text is gone! Sight a target on the horizon, whip over to your nav map, click on the colored silhouette and see identification, course and speed? Don't try that with TMO. Nerfed. "Fast" was a giveaway a narrow speed range. No more, you have to determine speed for yourself.
x on the attack map is gone. This one I don't necessarily agree with. The back end of the vector is still the torpedo impact point, so no real harm done, but comparing TDC data to actual position was central to real targeting. No captain would shoot a torpedo without confirming the value of his solution and many shots were stopped by the officer in charge of the TDC (could change from boat to boat) announcing "bad solution. Do not shoot." He knew this because he was comparing the position output by the TDC to plotted position and finding that they didn't agree. You can't do this with map updates off. A real skipper would lose his command if he were to waste torpedoes in this manner. TMO preserves your ability to perform this indispensible function without letting you cheat.
Is that it? I think so. I'm working strictly from memory on my work computer. So, what is the weakness of the TMO plotting system? There is one.
That is perfect positioning of visual targets on your plot. It's interesting. The mission editor lets you assign a spawn point for a target and say "start this guy within 10 miles of this spot." But it doesn't say, "Ok, this is a visual target, fog, rough seas, 4500 yards, plot this anywhere within 500 yards of its real position." In other words, the game could plot with a random error within a certain uncertainty determined by the qualities of the sighting, but the devs chose not to. They had already done 9/10 of the work in their mission editor!
In the example above the 500 yard uncertainty could be different, based on visibility, range, sea state, sub crew experience, etc, so that each sighting would have its own tailored uncertainty. The position would then be plotted in a random direction and with a random error up to the uncertainty number in position. Add that to the wishlist for Silent Hunter 5!
So what do you do? Throw out the baby with the bathwater, kill the map updates, drive your sub with a paper bag over your head and claim you're playing realistically? Or use the TM plotting system and just don't take any measurements off visual positions?
I think I'd have a problem deciding if I had a boat without radar. Neither would seem right and I might end up turning map updates off, although that would also kill my air radar: an unacceptable situation. I'm not happy with either way if you don't have radar. You might be best served using
TMOplot and not measuring anything from a visual position on the nav map. It's not perfect but its the best we have for now!