Looking for Tips when Dealing with Ninja Aggro

[Adrasteia]

I just ran Toto-Rak last night, with a L27 sync'd NIN and an L24 ROG as our DPS. I was a sync'd-down i90 PLD with Zenith relic. The NIN could take a mob away from me *if* I let them (got lazy and slowed down in rotations) but plain old Flash and rotating RoH between mobs, I had zero issues taking it right back - and never lost the bosses or boss adds.

This has been my experience, as well. If I lose aggro, it's generally either due to the DPS not being on the same page (attacking two different targets) or because I'm not Flashing/rotating my combo on multiple targets consistently enough.