Can't read all these pages, only made it to page 8 and I'm already seeing repeated stuff. In fact, what I'm about to say will probably be a repeat of something, but I'd like to say it anyway.
The bad DPS aren't at fault here. SE is.
For some strange and curious reason, SE decided to throw DPS checks in every hard fight yet gave no one a way to measure how much DPS they were doing or any indication of how much is needed to beat the check.
Easy example, Warlord Shell in Ravana. The only thing you know is that you need to do enough damage to the shell to break it. How much damage? Are you contributing enough? Are others? You have no idea, you just hope and pray that it breaks. If it doesn't, what then? Give out general advice of 'we need more damage during WS'? What if the person (or people) who are holding the group back believe that they're not the ones causing the wipes and they're doing as much as they can? Do you kick them? If so, how do you know they're the ones causing it and not someone else?
It's dumb. You can scream harassment all you want, but as long as they implement DPS checks that need to be met in nearly every hard encounter in the game, people are going to complain about bad DPS not knowing what they're doing. This game sucks at incentivizing you to play well so when the time finally comes when you need to, you're kicked from the group and you wonder what's happened. I'd legitimately hate to be any player out there who expects the game to teach them how to play it and doesn't go the extra mile (like many of us have) to learn their class/job on their own, including researching optimization of their rotation and learning fights before even attempting them. That should be optional, that should not be a requirement.
Fight design in this game is a mess. It honestly is. There either needs to be an in-game parser or they need to stop implementing so many DPS checks. There is no reason why an MMO in this day and age should have such little information available to the player.