There's 3 Gunnery Cannons in Phase 2, I can solo heal the 2nd (Medica + Assize) and 3rd (no incoming damage until jump damage) comfortably.

The 1st one however, as a WHM I'll really appreciate it if the SCH can throw out an Indom/Succor to assist, as the DPS are getting hit on by the 4 adds, and the ticks from my Divine Sealed Medica II may not be enough for them to survive the 2nd Gunnery Cannon. Of course if the SCH is insistent on DPSing, it's a non issue on my part as well, I'll just throw down an additional Medica after my Medica II, but this will depend on the WHM's MP conservation skill.