[Skybird]

The "three wave doctrine" and the use of large, automatically rolling formations is the result of

- massive mistrust into subordinate ranks (loyalty in the face of lethal orders, competence) and the belief that micromanaging at the top level is the way to go;

- cheap equipement that lacked quality but could easily beproduced in huge quantity;

- WWII where the maximum concentration of firepower from arty and tanks proved to be the only way to defeat tactically superior German forces;

- lack of communciation capacity to coordinate more complex force setups that act individually in smaller subunits. If you cannot give all those orders needed for more agility due to lacking capacity to communicate, make more units (or larger formations) listen to the same set of order.