It's not as much complicated as it seems at first glance. It's only like wasting 20-30 torpedoes and then you know almost everything about firing them accurately.
But I think we lost the point. This thread was certainly NOT meant to be another discussion about what realism setting is the best, or which option is better than another.
What I ask is to make "no map contact update" option not equal to '0%' in realism, but some grater value (at least 1%, but I personally think it should be much more).
If it's too much trouble to change this one settings (then you have to adjust the others so that they sum to 100 points total), maybe making to highest total possible HIGHER is a choice? Let's say the max is 105%, and with map contact updates it'd be 100% 'only'?
I don't care if you get 100% of your renown when playing at lower realism settings. If you want to get 100% renown, get it and enjoy your game as much, as I and others do. It's all for fun, any way you play it.