I have not played since Vanilla so have no fond memories of raiding in game that was revolutionary for its time, but I feel like Healing has devolved.
I don't know how to put this--kind of without words.
The groups your LFD put together can't keep up with what you're asking them to do.
* They don't--the large majority of them anyway--care about threat. Recount-fever has them and there is no cure. Heck, the more time they spend dead, the more time they can fap over DPS (not Damage Done).
* They don't care about CC. They deem that if I'm a good enough healer, they don't need to CC which is unfair to me on many levels, including, trash mobs are actually dangerous now and 4 mobs attacking the tank instead of 3 is not 33% more damage necessarily. Depending on the mob you're not cc'ing, that mob might be 10%, he might be 100%.
* They don't care about mana. Wiping in heroics is not a common thing for me but I'd be lying if I said I hadn't done it. They don't like it when I oom and they'll pull when they think I have enough mana, regardless of how nasty the last pull was.
* In the group's eyes, I am the reason mobs need to be cc'd. Not danger to the tank. You could give a pull 4 mobs that hit for 20k a swing and decrease the groups healing taken by 25% un-cc'd each and when we wipe to that, healers would be blamed. Not the tanks. Not the dps. Me, or my other holy, resto, and disc friends.
Now you can fault me, I'm not in a guild, but frankly.. Wrath burnt me out on raiding. ToC did a number on raiding on my server. I had no problem getting groups to come back throughout the week for Naxx and Uld. ToC, once you were good at it could be done in an hour. I had difficulty for most of ICC getting groups to stick together, regardless of how quickly we progressed.
One might even say, once people saw and killed the fights, they stopped caring.
Whenever a complaint post about a specific type of player is made on these forums, it usually receives the reply: "The people you're trying to reach don't read these forums.".
Blizzard, forgive me but the people you're trying to reach don't read these forums, or your blog posts.. They don't know who "Ghostcrawler" is; referring to you as Blue, as we often do, gets a "Who? What?". You irrevocably changed the game in Wrath and all we're doing now, we who aren't in guilds, or aren't in good guilds, is being punished for how we play this game.
I know every mechanic of every heroics boss. I researched the stuff as best I could before launch and the re-researched it a week later when there was more information, and more importantly, updated information (where changes to certain fights might have been made).