Why does Square want Dark Knights to use Scythe, yet the man who teaches you how to be a Dark Knight exclusively uses a Great Sword?
Maybe he was PLD before he became a DRK, har har har.
And Sept, your questions are actually harder to understand than why WAR can't wear Guttler. The game SE had in mind wasn't filled with people spamming WSes and using the shit out of Dual Wield and Utsusemi. They probably thought a WAR had to be crazy to use an Axe(unless they were tanking with Axe + Shield, lawl) over a Great Axe or Great Sword. Maybe they didn't do the math when they added the RoZ expansion. Maybe one day, they will start using foresight.