I've yet to hear a convincing reason as to why it was necessary to have such small heals in order to make mana matter--the primary reason given for the changes.
I think you should really read this blog he posted some time ago. And not just skim over it and say "I know what he's saying already," but really read and comprehend his points.
Let me iterate to you mine, which reinforces the blog post:
Healing was literally brain dead. You asked a Druid, "What do you use to heal?" They would respond, "WG on CD and Rejuv." A Paladin would answer "HL. Just HL." A Disc priest would say "Bubble. Bubble EVERYTHING."
Despite the challenges that were implemented in the game, it made no difference. Heals were an answer to everything. It was an answer to a player's mistake of not standing out of fire, of not watching out for themselves or interrupting. Heals were the thing that was so rudimentarily easy to apply to every situation that it stopped being fun.
Well not only did it blur the line between good healers and bad healers, but it stopped being gratifying.
I'm sorry, but you can't convince me that it's in any way, shape or form gratifying to steamroll through heroics spamming nothing but one heal. It's not a challenge. It's not something that proves to myself "I did this because I played intelligently." It was "Yerp, HL's a great spell because it's so efficient."
Playing a game should generally be centralized having the player have fun. For example, today I went into a Heroic Grim Batol. Last boss we wiped about five times. Last attempt we performed flawlessly -- and would you believe that I didn't stay below 75% Mana the whole time? I used one CD: LoH.
It was exhilarating, my group performed as a whole -- well and it rewarded me with the gratification of knowing that it was challenging and that I am getting my money's worth and more. It took practice but after that practice we did it and executed it as needed.
I don't remember the last time healing felt that good. I felt relieved that I saved a tank before a global -- that doesn't mean It feels gratifying.
Being constrained to the game mechanics that can be easily answered isn't fun. (Wrath).
Being constrained to the game mechanics because there's something that my group did that can do better and will do better on is fun. (Cata).
In all, healing is fine. It takes practice, and a lot of it. Get the hang of triage and you will succeed. Run with guildies and implement rules. Don't be afraid to CC an extra mob if it makes it easier on you. Don't be afraid to CC something YOURSELF. If you need someone else to dispell something -- tell them.
Communication is the name of the game in Cataclysm. And when Pugs/Healers don't do that, threads like these is what we get.