Quote Originally Posted by Eorzean_username View Post
Kaiten's design essentially split 1 action across 2 buttons, since separating them was ~100% useless in all possible cases. So Iaijutsu was basically a 2-key combo... except it had no tangible effect, other than invisibly increasing your action to the correct Potency.
The tangible effect was to increase gauge management complexity and also to give you a hit of 'job fantasy' via an animation when you used it. Not every job element has to be an 'adds function'. Some of them can be a 'don't screw this up or it's suboptimal'.

C.f. the dungeon changes, where something was very tangibly lost when the design shifted from 'use your judgement to anticipate how much you can safely pull' to 'everyone lick the wall'.