Earlier quoted context omitted.
The article's description of submarine warfare is surprisingly similar to how modern air combat is supposed to play out, and parallels modern artillery's shoot and scoot philosophy as well. Hide, find, hit, and hide again.
Long gone are the days of the British soldiers taking a knee in formations to shoot their muskets. Essentially expecting to take turns with the enemy trading shots. Never did understand that mentality at all.
Also being in formation helps stop people from running. If all your guys are spread out in the woods, more than a few might take that chance to 'disappear' from the battle if not from the entire military. It is a lot harder to do that in a tight formation and you would easily get called out, or even potentially shot in the back, for deserting.