Hmmmm.... Is it just me or is the main problem being overlooked here? IMHO if you survived, you did just fine. That's point number one.
What is missing, however, seems to be several things. First, these things should all be settled beforehand. One of my fail-proof indications of the strength of a group is how well the group sets up guidelines AHEAD of the combat. Designation of who loots, what happens with uber drops, who pulls, who is the main tank, add tank, main healer, crowd controller, and on and on. If it's done beforehand I can guarantee you that the group will pull smoothly and kill efficently. You will also have occasions where a pull goes wrong or mobs pop on top of you or some idiot trains you in the middle of a battle. You will then find out who evacs, who CALLS the evac, and what the team is supposed to do while waiting for the evac to cast.....or not. If not, you will find out how nice it is to have clerics in the group.
How nice it is to be in a group where these things are all set in advance and while you still get the adrenalin rush and the heightened blood pressure, the end result is that the group survives, kills the mobs or smoothly evacs. Nothing is better than chuckling about these after the mobs are dead and ML is gathering the loot.
After a few of these, I have become somewhat of a curmudgeon about groups. I ask a few "innocent" questions about the group and if I don't like the answers, I find something else to do. I know it's cowardly, but I have tried to educate some of these groups and found it to be a totally useless endeavor. If the group members are over level 30 and still don't know what needs to be done when forming a group, they are lost causes. Go find something else to do where you won't be killed by someone you will probably never see again anyway.
By the way, a group with two clerics sets alarm bells off in my mind, anyway. If you have one good cleric, that's enough. If they are not good clerics, six is not enough. This is not a really hard rule, but unless you just couldn't find enough other classes to fill the group, there is not a reason to have two clerics. If you do have two, however, you really need to work together and set roles. One needs to be main healer, the other needs to keep the buffs up, and they both need to spend a lot of time communicating. Communication is the primary mark of a good cleric anyway.
One last comment if I haven't lost you already. When a group chides a cleric for lack of, or inefficient crowd control, it is definitely time TO GET A NEW GROUP. Sorry about that, but this games works best when each class does the things that they excel in. (my high school english teacher is whirling in her grave) Anyway, if there is fault in your experience, I fail to see how any should be attached to you, except in your choice of fellow group members.... I hope I'm not being too critical, but I commend you for listening to the criticism and trying to gain a better understanding of the situation. You will do just fine in this game.