I only just came across this interview while looking up more details on the MP/TP merger, which is dicussed in this interview also.

Press: On the subject of battle system revisions, you announced that MP and TP will be merged into a single resource. Are there other user interface changes in the works as well?

Yoshida: As you are no doubt aware, MMORPGs feature quite a few elements that players have to keep track of mid-battle: damage-over-time effects, ability cooldowns, buffs and debuffs, etc. Adding in yet another layer of resource management would be very challenging for the development team. To your point about MP and TP being merged, that isn’t necessarily a monumental task from an engineering standpoint, but we have to be extremely careful with how it will affect job balance. Even so, the party window still needs an overhaul, and the UI team is giving it their all to make sure everything comes together nicely.