Roman Legion in late Antiquity

[Flavivs Aetivs]

Nathan is right about the Ridge Helmets. Roman Bowl Spinning techniques often resulted in deformities, meaning high waste product even if the material was cycled back in. 2 and 4 piece bowls, like the Intercisa and Berkasovo Styles, respectively, were more efficient because you didn't have to get rid of all of your produced material.

As to the change in tactics, I support Ian Hughes and Nathan Ross here. The Romans had largely gone from Aggressive assaults to Defensive Warfare due to a change in enemies. Some generals liked to starve the barbarians out, like Constantius III did to the Visigoths, while others preferred to be aggressive, like Aetius' utilization of Ambush tactics and surprise attacks like in the Battle of Mons Colubrarius where a large number of Goths were slain... man the Visigoths can't catch a break these days