A few weeks ago TIC last boss overcooked attack (when he chain the tank and burn it), was to weak doing like 50k damage, now its doing like 300k damage per tic... 2 sec and dead. That not a heal check its a death sentence. maybe with pally heal and temp shield is easyer but with DC healer there close to no time to heal.
Specially when my tank with 1.060k HP out sides get scaled to 830k hp... 50k was to low, 300k to much even with all damage reduction like mount/arti/encounter power... 2-3 sec dead.
If the party doesn't kill boss fast, after 5 phases there no more tank in party.