Two questions about cavalry weapons and infantry swords

[Geticus]

Vegetius is a useful source but you have to remember his purpose, he wrote the epitoma rei militaris after the disastrous Roman defeat at Adrianople c. 378, so his whole view had to do with the denial of rising Germanic power, and a sort of pompous revisitation of old Roman military principles. The Romans fought in rigid massed infantry formations which minimized personal heroism and instead put the emphasis on massed javelin showers, superior armor and overwhelming endurance. The gladius was as often as not the means of dealing the coup de grace to an enemy already wounded or impeded by pila showers, and exhausted by the grueling press against the Roman shield wall. So I think it is dubious to attribute the millions of men killed by Roman infantry to the superiority of the gladius per se. I know of not one Roman military history that makes a central theme of swordsmanship. Roman history instead puts the emphasis consistently on superior raw manhood (virtus), and military discipline. Celtic warriors who fought against Romans did well during the early period, all but destroying Rome in the early wars, and likewise remember that Celtic warriors held Hannibal's center at Cannae and successfully withstood the impetus of one of the largest legionary armies the Republic ever fielded. So to say that the Romans killed millions of Celts because the gladius and point weapons> edge weapons strikes me as simply a repeat of the Classical anti-barbarian snobbery. I would just as soon say that the Romans won with defence, not offense, and that the gladius was effective because it worked within the Roman legionary framework which prioritized endurance and tactical discipline over offensive flair and aggression.