Independent Units- Why?

I keep seeing the call for independent units back and as someone playing through N:TW at the moment I cannot understand this. At least in the old format.

Having to watch half a dozen or more single/ double units walk around the map is agonizing.

Chasing down multiple single entities is a pain in the ass (I can see a case for detaching some units to clean this up but then you're just multiplying the problem). Whether it's to block them from reinforcing or just to clean up a beaten unit it is still a pain.

IF it was to return I would say it would need a limiting factor. Such as a pool of "captains/ officers" that let you detach units from the main army. This way you can clean up units without committing your whole stack. It does open up the possibility of raiding supplies/ preventing reinforcing units.

I think Ultimate General: American Revolution revolution is doing this well where you can have units without a general but can't engage in a tactical battle. All though there are far less units on screen moving around at the moment than usually is in a TW game.

Edit: Mostly just seeing HOW people think it should be implemented if they did want it back. That's not just a 1:1 of the old system.