Centurions

[Robert Vermaat]

Being at the front and holding a gladius and a shield, the Centurion would probably be in no position to give any sort of commands other than verbal, so it's my guess that such commands would have been conveyed to everyone else by means of the horn, which is likely to have been near the centurion. Failing that, such commands may well have been conveyed with the signifier waving a few pre-arranged signals such as side to side, up and down etc, and it was probably the Optios job to keep a lookout for such signals and reinforce the message. The notion of eighty to a hundred closely packed guys fighting a battle being able to see the Centurion clearly is just never going to have happened.

Exactly. Even without being in battle, voice commands from the front can be overheard, so my guess would be that any ideas about units turning smartly about as one body are complete modernisms.