First, nobody mentioned Dark Knights, and I'd rather they be Sword & Shield anyway. Second, two-handed swords would be a third weapon type that Gladiators would get(along with standard swords and daggers). And, third, two-handed swords will likely be put into the game with a brand new class, which is probably the best idea.
If you didn't read the post I was responding to, the poster said nothing about two-handed swords, and only mentioned that Blue Mages/Mystic Knights shouldn't be allowed to equip shields if they came from Gladiator.