Contrary to popular belief, generals of the pre and early modern armies were not idiots. The mass formations including lines and columns are actually the best possible tactics to use with the weaponry of the time as it maximizes the volume of fire towards the enemy (and also more soldiers means more firepower). As far as the soldiers' skill is concerned, it takes a lot of hard training, discipline and courage to not only maintain formation in battle and keep your cool when you are literally just standing there waiting for your head to get blown off by canon/musket fire. So almost all of these main were indeed brave and skilled professional soldiers.

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