I was doing majordormus on my weekly run for the mount with my warlock. Since I was the only one in the raid besides my voidwalker, he constantly jumped on me. Below 50% I simply stopped moving since my shield absorbed the damage from the fire that stays where ever the boss jumps to. And I was too lazy and doing enough damage already to care about the buff.
Normally when you take damage while having the bar filled, the bar empties itself. Thats what I saw everytime I tried to get out of the fire. I was too close to get out in time. But when I stopped evading the damage and just stood there, taking the fire damage, the bar did not move. Neither up or down. He continued to jump on me on that spot until the end of the fight but the damage is negligible.
Fight majordormus
Not be the tank
Hopefully be ranged
If boss jumps you, run so you dont get hit by the fire that stays at the spot the boss is hitting with each jump
Repeat until your bar is full
Stop moving if boss jumps you
Bar will not deplete
Kill boss.