To be honest outside of extreme and savage content I don't really care if the healer aids with dps or not. Worst case scenario I may have to pull one pack less during chain pulls in DF, Id still be pulling 2 packs minimum so who cares.
Tanks are not pushed to stance dance especially in DF, but that does not mean we shouldn't, if the healer wants to only heal us tanks can just go out of tank stance sooner. Its kind of disgusting tanks can stay in tank stance the whole run and receive no grief.
From the man himself;
Yoshida: Yes. Since all DPS jobs will be increasing up through level 60, it makes sense to have the white mage's DPS extend by a proportional amount as well. For development, such as with Bahamut's Coils, the development team assumes what the item level should be for general equipment on players when they clear a raid. They sum up the basic DPS for four DPS and tanks at that assumed item level and cut that by about 10-15% for the minimum clear DPS. Healer DPS is not taken into account when this is set.
The only reason healers are expected to also do dmg for the types of content yoshida mentions is to speed up the kill time.
Will this stupid debate, ever do or don't ever end... Probably not in my lifetime.