I'm at around ilevel 576.
Even players who are just in flex or LFR gear out gear these instances immensely. If a DPS player in full SoO LFR gear goes into Mogu'shan Palace and decides to pull more mobs than the tank was ready or waiting for, he or she can probably DPS them all down before dying themselves, especially if they get a few heals. Meanwhile, even the tanks can often put out enough damage (while taking so very little and having various means to heal it up) that they can basically solo the whole place if they want to, leaving absolutely everyone in the group feeling very little need to actually play as a group. As many, many people point out to me on twitter, it's just assumed that everyone is going to pull like crazy, so even undergeared players in a specific role often assume it's going to happen and react. Maybe your tank doesn't want to pull like a fiend, but they saw your gear and thought they had to in order to keep control of the dungeon. The lines of group communication have broken down into a silence that masks intent - runs are zoned into and pulled with grim efficiency.
Into this veil of silence enters you, the player. So what can be done about it?