The way I see it, the devs answer to this speed running plague was to make it so no matter how good your gear and strategy was, that there was only so much you could get to with out curb stomping a smaller group. Snow Cloak rooms you could pull maybe a few packs at once before you got to a gate that wouldn't open till they were all dead. As well as Satasha HM, Quran HM, and now as of AK HM Agrius, and WP HM it's become the norm. You speed runners had your fun curb stomping things in 5 minutes in 2.2 and 2.3 well now the devs have decided starting in 2.4 that they aren't going to let you do that any more. Adapt or go play WoW where they still allow pulling the whole dungeon at once.