Picture leads to more philosophical question, how many holes can a wall that doesn't exist contain? Luckily for us during 1700s Scottish philosopher
James Keith studied this problem and found out that at least three and maybe more....

Secondly, when you start the main campaign there is columns in Elbe army that cant put back to army chain of command if taken out of it. This is because those columns have commanding officer forming a brigade. Now it you open that brigade you can assign that column to different army, but does that column behave differently (meaning fight more poorly) when those units are in opened in the force ?
Thank you.
EDIT : Changed the pic to a better one