This may have been covered...
I remember reading a paper several years back, about Latene blade length being related to an increase in the use of larger horse breeds. As these weapons were used by the horse and not the foot, for greater reach. I believe that much later, the development of swords that could be effectively used with two hands have tangs, not so much the hilt, disproportionate to the length of the blade when compared to the single hand grip. This is for leverage, with a space between the hands, which is translated into the speed of the blade's end, the great advantage the clay mor has over other swords. There was also an issue of the type of metal used to prevent breakage. Again the two handed grip has a very long tang. Without the support of the tang, a longer hilt would simply soon break or shatter upon repeated impact.
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