I did my trial roulette yesterday and got Steps with three first timers to boot. We downed Vishap with one dragon killer left to use on first attempt. Of course we took the time and asked who was new, had previous multiple clears and what everyone thought was the best course of action. It was like watching poetry in motion, so precise, so... right. All because of a little communication and some folks stepping up to do mechanics. If people aren't clearing it, it's because of two things:

1. Either someone or some people can't be bothered to do it right as has been stated multiple times I am sure. You can't zerg through this. Vishap is laughing at your meager attempts to harm him with weapons outside of cannons and dragon killers.
2. There is a miscommunication or no communication at all in regards to what should be done and who is doing it. Of all the trials this requires teamwork. From the tank down to the dps there is a place and time for practically everyone.

In short the disbanding is not because the trial is "hard", it is because people can't be bothered to play as a team. If they can't be the hero of the parser then they don't want anything to do with it most of the time.