That's for sure Notewire
I'm currently at the western approaches and decided to patrol here instead of my assigned grid (too far away). I went down to take a hydrophone reading and picked up a ship in the east.
Now previously (before this mod) I'd turn around and
star-trek myself down there, sink the ship and go elsewhere - no problem.
This time:
I note the time.
Turn around, surface and max speed - take notes of speed and course.
While on the way Fix my turn-around position.
When ship is sighted note time (calculate distance travelled) and begin attack. i sunk the ship by gunfire as the sea was flat.
Then returned to original course, taking notes of time, speed etc..
With all these times, speeds, courses, etc I use the Marker pen to note my current position.
As you all can see, it's a s.h-i't load more work to do, but if you think about it in RL, this is no more than what you'd do on a sailing boat.