I can life without a tail in the map, and is easy to know the heading where the ships are sailing.
Mark with the tool, wait some time and mark again, use the ruler and draw a line. and you have the heading of the ship or convoy.
But i like have the tail because is easy have the overal situation in a kick view and save a lot of time. and finally and the most important reason is because i´m the commander of the boat and there are officers that make some work for me, like obtain headings, and other data.
I have enough with the important tactical decisions and give the correct orders to the crew.
In this case i probably use a little mod or a file for the tail in the map

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With tail or without tail GWX is Great