Good points.
Another thing to remember is that most of the killing on ancient and medieval battlefields occurred in the pursuit, after a formation was broken and the losers began to flee. This is simple enough to visualize. We don’t know nearly enough, however, about the opening phases of a general engagement. What was the individual spacing on the line? How deep were the formations? What was the structure of both formal and informal combat teams and how did these units function in battle? Presumably both infantries would have tried to keep ranks. Presumably experienced warriors would have understood the need to avoid crowding. Presumably small teams, formal or informal, would have been formed for mutual protection. We just don’t know much about it.
There are hints in the literature, and some of the Roman terms have survived. The word escapes me at the moment, but the Romans had a term, for example, for small wedge formations that would attempt to penetrate an opposing line. I imagine one or two legionnaires at the point, and maybe ten or a dozen covering flanks and rear. All rehearsed and part of small unit battle doctrine, but largely lost to history. I would guess that professional soldiers in medieval armies had similar tactics.
The movies tend to show either stylized duels, which one understands as a dramatic convention, or massive, formless brawls. What is left out of the picture is the broad middle ground of well-practiced teamwork at the small group level.
I think that “tactics” as they have come to be known, were pretty much limited to intitial formations and the handling of reserve forces. Given that “history” was a new field there wasn’t a whole lot of importance given to systematically study of “what happened,” simply a recounting of brave deeds with a view toward propping up the legitimacy of the conquerer. It’s a shame really.
I remember a re-enactment of the Japanese advance down the Kra Peninsula toward Singapore (1942). A few British military engineering officers using some basic wooden pilings, rope & planks supervised a rugby club in a simulated bridging operation to illustrate the fast, improvisation required by the Japanese thrust. It was amazing how well a cohesive group could “figure out” what was necessary, and not, with almost no instruction. They basically got it right.
I imagine that if you took a 2 companies of soldiers... pit one against the other with period weaponry and historical objectives... they would figure out the entire tactical system in short order.
Tercio?
Centurion Lucius Vorenus and Legionaire Titus Pullo breaking the Gaulic shield wall at Alesia? (HBO's "Rome", Season 1, Episode 1)
You see the front rank of Vorenus' cohort (maniple?) forming a flying wedge to pull a cut-off Legionaire (Pullo) who broke ranks in a rash attack. It was pretty interesting to see how the ranks rotated to keep the front-line fresh.