For Dervy and t11, the guys covered up pretty everything. It depends on your DPS to say when the phase will shift, but keep in mind that, if a Nerve Gas started, she will do the full rotation (till Second Head) before move to the center and drop the shield. I usually stay on her left flank on 1st phase, then end up in back/right flank at 62% to wait and see if she'll change the phase or just do a full rotation. Just keep in mind that, if your tanks mess the pull a little bit, she may move in a "strange" way to the center of the room, and if you are close in this moment, you may get into the Barofield and screw your 2nd phase start.


For t13 initial burst, I have a lot of trouble with my tanks too. If I'm feeling lucky with my latency, I'll drop the circle on left flank (my position), go to the stack point, wait the red circle resolve and come back to my place befor ppl come to stack (or at least before the damage). If i'm with latency problems, I'll just get into Bahamut on wichever space I can get and then come back. When I go inside Bahamut hit box, I may eventually miss an auto-atack, but at least I can keep my rotation up. On the last scenario (ppl come drunk to raid), I'll run back, miss my skill but keep alive (and sad). Everything assuming I got the red circle but not the stack mark, of course.