"However, artillery being captured, turned around in the heat of battle, and starting firing on the troops of its previous owners? Unlikely."
That's probably right (can't remember any counterexample), but the same argument could be applied to ships, and that's going to be in the game now. It’s like proposing removing the building of towers because that didn’t happen while a battle was taking place meters away. It's all a representation of things, numbers and time are shrunk with respect to what in reality would have been, it seems to me that completely removing something that happened just because it didn’t happen in the same battle is the wrong call. Capture times would have kind of prevented turning things around in the heat of battle, and if not, a “use cooldown” could be implemented, one being able just to move the piece in the meantime. Edit: I think something like that was proposed for towers and fortresses, to avoid turning them around fast, although more from a gameplay perspective than a realistic one. For ships it would also make sense to have a use cooldown.