Here's the thread the poster's main thesis is that nearly all combat before the advent of gunpowder consisted of groups of combatants utilizing limited ranged fighting before cautiously inching to the opposition, fighting for a short burst, and backing away to regroup.
I've heard this before (on this subreddit) with people describing it like "boxers breaking back to their corner at the end of a round".
I was wondering though, because historians emphasize the significance of discipline in ancient armies, and how this may be in place specifically to negate this pattern.
I've also heard there's scant evidence on the actual patterns of roman combat.
Is there a consensus on this?
There are several theories, however, from what I've read, that poster is rather accurate. "Modern consensus" is always a tricky term to use, due to the fact that everyone has a slightly different idea of what ancient combat (You refer to Rome) looked like - and I'm afraid that the most accurate answer we have is that we honestly can't imagine it. However, one predominant theory, championed by Adrian Goldsworthy, does agree with that sentiment. We know for a fact that the armies spent most of their time probing for weaknesses (Each army would form up on their preferred part of the battleground and dare the opponent to come to them - think of an ancient game of chicken). During this time, skirmishes would take place between the cavalry and skirmishers - and this could last for quite some time (days/weeks, depending). During this time, it wasn't just the armies facing each other that would sap the other army's morale - it was the supply situation (which is, incidentally, one of the reasons the Romans did so well in...for example...Gaul. The tribal armies didn't have an organized supply line, and while Caesar outran his every time he felt like it, Rome's system of logistics was BRILLIANTLY managed). The armies might be placed slightly closer to each other every time, until there was no choice but to fight - and then it was on. However, the stresses from being in close combat (physical and mental) for a protracted period of time would make it so that combatants would clash, trying to break each other, before seperating to catch their breath. During this time, they would toss any remaining projectile weapons at each other, as well as insults, taunts, etc. Then round two would begin!
The thing about Roman discipline is that it was in place to keep the men fighting. This backing off was still considered fighting - the men were just catching their breaths. Disciplined men were MUCH less likely to panic and break, which is when the killing in a battle truly began - which is one reason why our casualty figures in the ancient world were so incredibly lopsided. When men broke and routed, the slaughter would begin by the victorious army. Obviously, another issue here is when the victorious army gets too carried away and began to sack/loot/rape everything in sight - a situation which could give the defeated force time to rally and counterattack the now-scattered "victors." This was another example of Roman discipline, interestingly enough - the discipline to not "go nuts" after a battle. Even the Roman looting system was systematic and carefully controlled - which speaks volumes about why they did as well as they did :)
Hope that answers your question!