I Hope The NPCs Stand in The Fire

 I hope the NPCs stand in the fire, and if you don't triage properly, you fail.  Yeah, just to test their triage skills, one of the NPCs should, in the middle of the encounter, drop to, say, Cheapest WoW accounts 25% with a DoT that will progressively take the rest away. That'll test their "OH **** HEAL" capability, and their ability to not get tunnel-vision. Well, if they wanted to be realistic, that 25% with DoT situation will happen at the same time as the tank taking some spike damage and another DPS taking completely avoidable damage.

Dispel the DoT, throw a HoT on the 25% player. Shield if it's available to your class.

Wind up a big heal on the tank.

Let the derpy dps either realize they're standing in the fire or die.

 Actually, I would take the opposite view.  If someone continues to stand in bad locations and take massive amounts of damage, I think the Healer should get bonus points for prioritizing the heals.

A group that wipes because the healer goes OOM trying to keep one silly/bad DPSer alive is a total wipe, as opposed to when the Healer is aware enough to let the "baddie" die to save the Tank is showing skilz.

 Totally agree with you Kensdisguise2.

I've healed a Lei Shi fight (the water elemental) where a few dps stand in front of the boss (where only the tank should be).  When I was a young/naive healer I used my big/fast heals on them as much as I could to keep them alive (and was always out of mana before the end of the fight). 

Now that I've gotten better at healing. Buying world of warcraft account I'll throw a Hot on them (if they get out, they should live and I can heal them again).  If they don't get out, they die, and I save my mana for more important things.

(Now if no one else was taking damage I may heal the bad player for fun--but I would probably do more good attacking the boss.)

This is correct. Do the DPS whine when someone fails a mechanic and an add spawns that needs to be killed? Of course not.

Do tanks whine when somebody pulls an extra trash pack or spawns a mob during an encounter? Well, sometimes, but they shouldn't. 

The point is to work as a team, not to play god with your teammates.