Khanagi of Maelstrom sent out a plea in the official forums for players to be prepared when they group up for a heroic instance. His main complains is that as a Warrior Tank, he is often out DPSing the DPS. He feels that everyone in the group has a job to do, and many are falling short of their appointed task. His sentiment was met with considerable agreement from responders, who pointed out that AOE tanks will often have high DPS. This does not excuse the DPS from their responsibilities.
Back in the day, when Burning Crusade was launched, one had to be revered to get their heroic instance keys. This meant you had to grind out reputation with a particular faction to get the heroic key, usually through the highest level instance. This changed in Patch 2.3.0, which lowered the requirement to honored. At that time, there was much rejoicing. Honored reputation with a faction can easily be achieved with leveling quests. You no longer have to cross the threshold of a dungeon to meet this requirement.