You can completely ignore the Sonic Breath skill on Atramedes air phase, be it normal mode or heroic mode.
The exploit just consist on your whole raid going to the very end of his room as the Sonic Breathes will not reach this place(until fixed) making the whole fight much easier.
You can see it being done in video on Tribunal's kill video: YouTube - Tribunal vs Heroic Atramedes 25man Warlock POV @ 2:15