If this is an exploit then so was being a NIN tank in XI. SE never intended it; it was supposed to DD as well as debuff, but the players saw different potential and ran with it. SE are good about jumping on things they see as exploits, and they haven't done anything about this. It seems to be an intended option for players to collaborate on.

One can (and several have) make the argument that it's cheap, but you know what? FATE is cheap even without the ability to cash in big on a particular one. You can't complain that people are losing out on a learning or fun experience by not-making grinding take as long as humanly possible. FATEs often amount to mindless aoe spamming, blind voking, and the healing of people who don't need it. It's not like people aren't learning their jobs because they aren't doing FATEs for long enough.