Short Sword Underrated?

[Urselius]

Gentlemen, are you two attempting to overturn the commonly accepted disappearance of the gladius from the late 3rd ccentury onwards?
Some points of thought:
1) Republican auxilia infantry also used the spatha. If this was a case of fashion would they look 'with envy' at the auxilia cavalry or the citizen legionaries?
2) What 'high % Cavalry soldiers of the era' are you referring to? Certainly, cavalry increased in number, but not excessively so: when we know the numbers, even the highest percentage of cavalry in an army never exceeds more than 50% of the total.
3) Even if the mattered, Late Roman arms were manufactured solely by the state. So there in every reason to accept that the adoption of spathae by infantry should have been centrally directed. It could not have been a case of fashion, because the state decided what to provide.
4) the number of spathae vs. gladii/semispathae turning up in the archaeological record of the period after the 3rd. c. AD is clearly showing that this was not a case of 'number' or 'fashion', but a change in style.
5) Afaik there is no iconical reference for the gladius after the 4th c. in late Roman portrayals of soldiers (excepting retro-art of course where the style is either hellenistic or undatable).

I could go into details, but my basic thesis is that military equipment sometimes changes without there needing to be a practical reason for it. Consider the appearance of armours with plate codpieces from around 1520. One could raise the premise that they arose in response to the development of a specific "ballock-attacking weapon" which needed to be guarded against. However, we know that the new armour element was just an expression in metal of a clothing fashion.