Right now on live the best way to kill groups of mobs is to heap on AoE attacks. By upping the mobs hit points you haven't changed that fact.. if anything you've re-enforced it. If you really want to address the AoE problem you need to either nerf the AoE attacks or up the hit points AND the effectiveness of the single target attacks. This was obvious before so I'm not sure why the AND part got lost.
This is especially true for those low damage single target attacks that the tanks and controllers have to depend on (especially mind controllers that get no pets, or any controller from levels 25 to 32). The increased hp regeneration due to those added hit points is going to be a nasty thing to overcome for a low damage dealer when facing an even level boss.
