As a SCH, I DPS as much as possible in any content, its part of the reason I love the class, lots of DPS and strong quick heals, as well as the fairy heals taking over for most pulls.

If a healer doesn't want to DPS, that is their business, although if a tank isn't using cooldowns or using them very poorly, I often have to forsake DPS completely to make up for them being inept.