Yeah, most of the fighting wasn't exactly the kind of shit they write heroic poems about. Pillaging was the primary tactic of the day, mainly because while we like to imagine epic conflicts fought over freedom, faith, and murdered princesses, most wars were fought over economic issues like property rights. Since peasants were essentially a resource (they provided food and tax revenue), terrorizing them was an easy way to hurt the enemy without the risk of taking an arrow to ye olde gonads.
Universal Pictures
The trampling of Maximus' wheat crop should have been its own trilogy
On the rare occasion when large battles did happen, only armies commanded by total bozos would descend into the usual trope of two forces that fire a few rounds of arrows and then start hacking at each other in a chaotic free-for-all. Scouts and spies were used to track enemy movement, armies used terrain, trenches, and tactical positioning to try to gain an advantage, and they would, you know, try to hide their forces if possible. Commanders studied past battles and textbooks were analyzed and revised. Again, they couldn't throw waves of men at each other. They didn't have them to spare.
So every scene in which a hero leads a courageous charge into the teeth of of the enemy is actually showing that he's kind of an idiot. A true hero would be slaughtering confused peasants and stealing their cattle, dammit!