To answer your question, it stopped most people from easy mode bombing but I was in good organized groups that continued on through organization. We ran with 2 groups each with a sorc and choppa. We would wait until we had morale 4, which was easy to get, even in scenarios. Then 1 sorc dropped the specced for the 7 second morale 4 root which was unbreakable, and the other sorc specced into the 100 foot ranged 20 foot 7 second aoe silence morale 4 to shut down clumped healers.
We just pre-dotted with chillwind, icy spikes, applied the morale 4's, then went in to disastrous cascade. With the new Close Qaurters, it made shattered shadows (the ranged AOE) a 1.5 second cast instead of 3. Since the spammable AOE Surging Pain was nerfed to not build up dark magic, all you had to do was alternate it with other spells to go from 100, to 80, to 100, to 80 dark magic. It was still usable.
So you go in and hit Distarous Cascade (the channeled PBAOE), Surging Pain, 1.5 sec Shattered Shadows, Surging Pain, then Infernal Wave spam. With the tactic Never Ending Agony, Infernal Wave's Cooldown was reduced to 5 seconds

It was a fully functioning bomb group reducing city warbands to vacancy after 5 minutes, and worked fine in RvR for flanking keep sieges or other large scale fights. It was great in scenarios as well. The Chosens spammed the AOE debuff that made all spells non-defendable with non-defendable talismans in their weapons, and every member of the 12-man ran Kamen Ra, so nobody had any Action Points to fightback, CC, or heal as there was no hidden immunity for how often they could be leeched.
The real end to real AOE bomb groups was server merges and player population dying, including our own rosters.