I really doubt this is intended to hit a nerve and nerf Ninjas out of spite as it is made to balance things out a bit. You have to admit that the ninja's advantage has made other tanks like PLD seem less desirable, which kind of ruins the enjoyment value of that job for many...some jobs are just better at tanking, at dealing damage then others to quote Berticus. And if people who love a job for the sake of that job can't get a party because they're always being put down, what's a guy to do? The same analogy can be said for Rangers and other DDs.
And I doubt this is trying to stop Ninja Tanking. Because NIN tanks are here to stay. They do their job and do it well. I see this update (or downgrade) for NIN tanking as just having them consider more options to hold hate.
Of course, at what cost? It's already hella expensive as it is...
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