The perennial topic of incentives for healers has crept back up to the top of my blogroll over the last two days.
The steep learning curve
Rohan got tired of not being able to find groups and respecced his Pally for healing, only to be surprized by the learning curve.
The closest I've ever come to serious healer like activity is click-casting decurses with my mage, and, frankly, I found it stressful in group settings. I was asked to join a PUG raid on the Obsidian Sanctum the other day (aside: don't PUG OS unless you're absolutely sure the group doesn't contain multiple players who won't move out of the bleeping wall of fire because it lowers their personal DPS numbers) for the sole purpose of decursing on trash, and I frankly semi-failed that extremely simple role because it didn't occur to me to drag out pet health bars from my UI (and good luck doing that in combat if you don't know where the option is).
Point being, I don't see how you're supposed to learn to heal if you don't already know - heck, Rohan healed raids extensively in TBC, and he sounds like he had a tough time getting back into it. I guess you can always try to heal stuff that's 10 levels below you until you get the hang of it, but that's a fair chunk of patience.
Syp's got a good summary up on healing incentives and disincentives. It's worth noting that I actually liked Warhammer's Rune Priest, I just hated being the first to die in a flurry of focus fire in every single skirmish. My solution to this problem was to reroll Witch Hunter and go inflict the same punishment on other fledgling healers, so not only did I give up on Warhammer healing, but I might have helped drive others off from it as well (sorry, guys).
If/when I get around to giving Warhammer another shot, I should really try to find some friendly bloggers willing to babysit a new Rune Priest up to a high enough level to see if I like the class better with all its defensive tools.
What if this is NOT an incentive question?
Much as I hate to ask that question, part of me wonders if the problem here isn't the in-game incentives as the out of game ones. Healers face an out-of-game learning curve as they try to adapt to group tactics, which are typically very different from solo ones. Healers face out of game pressures for performance that generally serve to raise their stress level disproportionately compared to other classes. If the tank isn't putting out enough threat, the DPS can slow their damage, and, if the DPS isn't doing enough damge, the tank and healer can try to cover with longevity, but there's no helping it if the healer can't keep up for whatever reason.
What makes this tough is that it isn't something that a dev can solve by throwing achievements, contribution, loot, etc at it. Those are much easier fixes than social pressures that the devs have little control over. Short of designing a game with no healing whatsoever, I'm not sure how to address this one.