My group does rotating healers rather than static healers. Static tends to interfere with melee more and it never quite works optimally. The way we rotate is that our tank pulls ifrit to cardinal north, I (WHM) start on the west side, and the SCH starts on the east side. We each focus target the other (important.) If the east side gets debuffed first, we both stay in place at east and west until west side gets debuffed. Once west side is debuffed the east side healer moves in to the center with the group. That healer (the one in the center) will watch the status bar of the other healer and when their debuff is at about 3 seconds you switch places. So the healer about to get the debuff moves west, and the other moves to center.

You pretty much keep this up the whole time, with the exception of the nails. During the nail phase the healer with the debuff is on the west as normal. Our DPS start clearing nails on the east side and work clockwise, the non-debuffed healer can go with them to AOE cure. By the time the non-debuffed healer is about to get the debuff, the east side is clear of nails so they stand there instead of going west. Once nail phase is over you go back to healer on the west side. Note: the cardinal directions get screwy due to plume placement; use the same relative placement but you won’t be direct west.

If you’re rotating its very important to watch your debuff countdown and your co-healer’s. This gets difficult during chaotic nail phase when tanks are swapping and you’re AOE curing the melee, but once you get accustomed it becomes second nature.
Good luck!