Whargarble about Medica II...
There are three kinds of WHM's I've seen:
1) Enmity Adverse - They only cast HoT's as needed, never proactively, and DPS for the DoT's/effects not for the damage.
2) DPS Adverse - They will never use DPS skills, ever, not even DoT's, but will use HoT's and StoneSkin whenever there is no reason to use Cure alone
3) DPS Aggressive - They will prioritize DPS skills, which means they will do everything possible to maximize their DPS. This includes casting Medica II, Regen and other healbombs immediately followed by CS.

The Enmity adverse healer is trying to make the tank's job easier. The DPS adverse is trying to make THEIR job easier. The DPS Aggressive WHM doesn't care if they are helping or hurting the party. See previous threads about DPS-class healers lowering their DPS because they believe their healer doesn't know their job.

If someone wants to maximize their DPS time as a WHM, they need to tell their party that, otherwise they are just making everything less efficient all around, from pissing off the Tank with healbombs to pissing off the DPS by requiring them to heal themselves.