If everyone currently in combat jumps off of the sides in Vortex Pinnacle you will not die, but be whirled back up. But, in doing so, the mobs will reset back to their positions and lose combat.
I haven't had a chance to test it with any bosses. A free fight reset with no penalty is nice. Just be careful where you jump off. It might throw you back into the middle of the previously reset mobs.
To clarify, everyone in combat with the mobs needs to jump off in order to reset them.