healing is incredibly overpowered in this game before 50. they have plenty of time to do deeps in between a single heal that fills your entire health bar for no resources..
even full dps spec works beautifully if they have a heal on their bar.
I have to agree with the first part of this. I've leveled a heal-specced Operative & Consular to 50, and am doing a combat support Merc now.
Before Red Reaper, a well-equipped & specced healer can easily split time between DPS and heals except on a few fights per flashpoint. If the healer & the tank are over-leveled for the flashpoint, the healer can productively split DPS & Heals on pretty much all the fights. Sure, it probably amounts to >1/3 of the DPS a dedicated Deeper does, but every little bit speeds things along.
It should also be pointed out that Smuggler/Operative healers have two resources to manage. They sometimes are DPSing not so much to dPS, but to pick up Upper Hand/Tactical Advantage. When I'm on my operative, if nobody really needs a heal but tactical advantage < 3 or is about to drop, I'm going to throw out a shiv or shoot down a weak mob.
But, I've never actually tried healing a flashpoint while specced for DPS. In fact, that strikes me as a pretty terrible idea for all the flashpoints after Athiss. All the heal trees include a signature heal ability at L20, and that ability is increasing needed except in seriously overpowered groups .. which is usually not the case with a PUG.