Totally, if every encounter were to be executed perfectly then GHT would be absolutely useless. However, the main cause of wipes is people not performing perfectly. The only reason healers are there is to make sure the raid can survive long enough to kill the boss. If the boss mechanic is such that, like on Razorscale, there is a fire put on the floor that can gib people in 2 seconds if they decide to stand in it then GHT can and will save people that other spells in our arsenal won't. It won't keep them indefinitely alive in the fire, but it will give them that extra second/tick of life before they die that might prove the difference between them dying and them surviving. If you do this only 3 times in a fight then that's 3 raid members you've kept alive. Granted, a priest shield would be a much much better way of doing this, and thus it's hardly ever worth taking GHT. In fact, I haven't used it once since Ulduar came out, but I can see why one would want it in very specific circumstances and thus there is no reason against respecing to learn certain encounters where it can counter raid stupidity. My mission statement isn't to convince people to use GHT all the time, it's merely to convince people that it has a niche and is not useless.

If you're assigned to raid healing on Razorscale, which would be bad to be honest, as healers all have to sometimes move and what's going to heal the tank whilst healers are moving if not HoTs? Anyway, it's hypothetical, so if you're assigned to raid healing on Razorscale, then GHT is worth speccing into, it's worth losing Nature's Grace, it's worth losing Revitalise, it's probably even worth losing Living Seed. Again, this is a very specific example and it's only if your raid is partial to standing in fires, but still - it's a niche.

p.s. I agree that we should just let the dumb bastards die, but I can't seem to stop myself for wanting to keep those green bars green!

I never said that. I said it's not worth the opportunity cost, which is 7 talent points and a glyph slot.

I think when you consider GHT vs. Nourish you have to ask yourself whether the extra health from the GHT over unglyphed and unhotted Nourish is really that important.

It's absolutely true that using Nourish without a glyph or 4T7 bonus and without hots on the target is absolutely inefficient in all sorts of ways. But if your mana regen can support it and there is no need for the extra 4k or so health on the cast then why not? Now that Nourish actually can crit fairly often, it's a very viable way to give someone ~6k or so health with no preparation or cooldown at a very small overall mana cost in under a second (if you have enough haste). Doesn't matter if it goes sub-GCD - it's still better if you can give someone that health sooner.

Sure talented and glyphed healing touch will do better job, but is it worth creating the whole talent tree and set of glyphs just so you can use HT on certain fights while Nourish will perform just as well? People don't have infinite health pools and there are other healers in the raid so when someone goes down to 20% you typically see immediately 8k or so incoming heals on his health bar - you throw your 6k in from Nourish and job's done - time to move to another unlucky guy.

So in my opinion it's mostly a matter what other healers you're raiding with and how you team up doing healing. If you have a very strict environment where noone will ever cast a heal on "your" target then maybe GHT is a way to go. But at least in my experience that's not really the case.

EDIT:

And to respond to someone earlier:
Well, that strictly depends on your raid composition. If you have no holy pallies in the raid, then someone has to do that job. Ulduar sucks without holy pallies. There is so many encounters designed for direct damage healing. In so many encounters hots just don't cut it where people get whacked for 60% of their life just to get whacked for another 60% one or two seconds later. If you can give them that 30% of their health bar quickly you'll save them, otherwise they will die. We have to now resort to rather arcane methods of healing if there are no viable options of healing direct raid damage, or this does become a total faceroll and in the end faceroll wins because it's just simpler and more effective - simply put there are so many cases where people can't wait for a rejuv tick, regrowth is just a plain waste of mana because the HoT is pointless with such widespread raid damage and the need to keep everyone topped off at all costs, and lifebloom just got too expensive in general to just toss it around everywhere (and it just doesn't tick for enough within first couple seconds). So what are we left with?

I like healing, I like playing druids, it's just disheartening how one-dimensional this became in this expansion - at least for me. Maybe it's just lack of holy paladins in our raids that causes this misery, but honestly I'm coming to conclusion that with exception for a couple of fights, it would be hard to justify bringing in a tree vs a paladin in Ulduar, given the choice and basing the decision upon purely effectiveness of healing.

Guys! I was soooo wrong about Healing Touch strategy! I have tested it on most bosses and compared it to rg/nourish and it really does suck =( Anyway, I am very glad that now i am sure which way to go. The only thing i regret is that someone new to tree raiding would run into my post and copy bad ideas. Just delete it, please.
PS: the only question that remains now (for me atleast) is wether to go wg/nourish/swiftmend or wg/nourish/inner , for now i am leaning to the latter.
Sorry for all the typos, kinda tired after 12 hrs of raiding )

My 25-man raid group managed to bring down only the first three Ulduar bosses, so my experience may not be sufficient to come to the conclusion that Blizzard changed resto druid healing mechanics not to the better. Before patch 3.1 we were a class with a somewhat strict lifebloom cycle restricted by the omnipresent global cooldown (which was dull on the long run). Our main job was to stabilize the MT/MTs with three stacks of Lifebloom.
After patch 3.1 we are a class who is most effective hiting the rejuvenation button every global cooldown, interrupted by the occasional Wild Growth. Healing predictable moderate damage is our strength more than ever. Four pieces of T8 will push our healing output so drastically that it would be most unwise to give us any different assignment. I don't think that healing as a resto druid is now more exciting than before. The question I am asking myself now is if healing became even less exciting... I wish they would have changed Regrowth or Lifebloom to a somewhat worthwhile raid heal. I don't see their usefulness in this particular situation.

Where would those 7 points go and what glyphs would you use instead? Most likely 5/5 Nature's Bounty and either Nourish or RG glyph. With GHT, there is no reason to use Nourish or Regrowth for direct heals, making 5/5 Nature's Bounty and those glyphs a very small increase in healing.
This is exactly why GHT is good, except you're refering to Nourish in that statement.

EDIT:
Yes, exactly. There is no reason to use Nourish or Regrowth for a direct heal. If you're using either to save someone's life, GHT will do it faster. If you're using either to top people off, that is usually not a good use of our time/mana. I will try to put it as simple as possible:

Ever use a direct heal to save someone (while Swiftmend/NS are on cooldown)? Use GHT.
Ever use a direct heal to top off someone that is not in danger? Let HoTs or "smart" heals eventually do it.

p.s. ty for the term GHT!!!

You cast nourish when other healers would be forced to rely on flash heal/lesser healing wave. In other words, if the target needs to be topped off NOW. Examples: Mimiron's napalm. Nourish hits as hard as flash heal, and crits a lot, and leaves a living seed. This is useful for continuous burst damage like napalm.

I see Nourish is just another part of our large healing toolkit, and so it gets used accordingly and when the situation warrants.

I use Rejuv and WG quite a bit of course, but Swiftmend (which I also use quite a lot) is not always available or I don't want to risk not having it up for someone who really needs it later (Hodir-type fight comes to mind). Nourish is a good filler in this situation. You can assume someone is going to top them off, but I personally don't like to. However, it's rare that I'll use Nourish when someone doesn't already have at least a WG or Rejuv on them.

Here are some thoughts:

Rejuv: good hot. always been, always will be. Nothing to add.

Regrowth: good spell to use when somebody in the raid took some damage and is about to take more.

LB: dodgy spell. I can say for sure I will use it much much less with 3.1.

Nourish: with some basic haste, it will go down to 1-1.1 sec every time it crits with NG. Crits 40-45% of the time (without stacking crit rating), adding a 3k Living Seed. Rejuv+WG is enough to boost it up to 8-9k crit heal with 4pT7 and Nourish glyph. With all these synergies, I really don't understand people that even compare this to GHT.

Healing strategy: main problem of many resto druids is that they see Nourish as a MT healing tool. Well, it's not. Leave MT healing to paladins/disc priests. Resto druids are raid healers and Nourish is yet another raid healing tool, just like hots. On most of the fights I spam around rejuv/wg and SM/Nourish on anyone that takes nuke damage. Well it obviously varies from fight to fight, but in general it worked really well.

Either rejuv/SM or regrowth are better for handling naplam. If you know the target is going to take more damage, why not cast a heal that leaves a hot?
I don't know if priests use flash heal or not, but it's not really relevant. We have other tools, namely RJ/RG, which are not available to them, so if they have to use FH doesn't mean we need nourish.

LB still has the same HPM as HL with a better spread so it overheals for less and is castable on a few targets. Getting an NG proc via a crit nourish is nice and all, but it won't help you unless you're spamming it. The 4t7 bonus is fading out and besides it and the glyph are only useful for tank healing.
I can see nourish being potentinally more powerful in a 10m setting where it's easier to ensure everybody is hotted. It just doesn't cut it in 25s, not as a raid heal.

In a 25 main raid setting, I'm using rejuv as a primary raid heal, throwing it out at anyone taking damage. WG on nearly every cooldown when the raid is taking damage.

On to the topic of nourish: As has allready been said, I am finding it really useful when someone has to be healed FAST, swiftmend is on cooldown and they are taking heavy damage. For example on Kologarn when a couple of clothies are gripped. A swiftmend on one, and then I'm finding the only thing I have time for bar a NS/HT is nourish spam on those being gripped.