I don't post on the forums very often, but since this discussion seems to be pretty constructive..
I understand what you mean by your original post, since you are healer, you want to heal and the obligation to DPS is not what you asked for. Sadly, the game is designed the way that healer has to, if he wants to be considered as useful as he can be. Its the same way with Tanks, who signed up for tanking to soak damage, and suddenly they are expected to stance dance and do whole lot of damage (thats why Warrior is so mandatory in HW). I am not saying its great design, but thats how things are.
As a raid leader in FC that does community raiding (NaCl, you might have heard about us, since Zodiark is pretty small), meaning raiding with every FC member who wants to, I deal with all sorts of people. We have tanks that do 600 DPS, and healers that do zero, and we have cleared A12S with plenty of those, around 20 people in total, so it is not completely unviable. It just took some time, clears and gear to make up for the DPS loss. So while our healers that do DPS cleared Creator during late October, since the ilvl needed to do so (on our skill level) was lower, others had to wait for late November / December, until we got gear and experience to make up for the discrepancy. It depends on what you as a player prefer. You certainly can find places to raid where DPS won't be required at all and people will be happy just for your presence.
For me and my FC, the viability of healer that does not do DPS starts literally at zero on the patch day, and increases as ilvl of people rises. At this point in patch cycle, I don't care if healer does DPS, as long as he can keep us alive during weekly reclears. =) This is mostly caused by us not caring about logs / speed kills or any other hardcore endgame activity, we care about clearing the content asap, and then farming it with as wide array of FC people as possible. anybody who cares about llogs / raid DPS / speedkills would probably not be as content with it.