In MOP classes were so strong that even level 70's could pull enough dps to beat the challenge comfortably. If not for the limitations of hit/glancing and entry requirements than a level 70 raid would actually been able to have easily beat the Herald of the Titans challenge in MOP with the numbers they pulled, probably also undermanning it.
It went from being a challenge that the majority of players simply would not be able to do, to where the only challenge was showing up. I'm not saying that as an elitist who did it when it was relevant... I had my chance to do it in WOTLK and I pulled out due to RL stuff, my guild got it with 2 players from another top guild on the server.. I didn't get it until MOP and it was such a joke... I'm happy to have the achievement but it's a joke achievement and the title is meaningless now because it should have been removed in Cataclysm.
It would be like having the challenge modes left in the game to be done at 90, but severly undertuned so that you could essencially solo the Gold. It is long past the point where removing Herald makes any difference any way.