I don't think LFR hurt DS at all, I think it was just HM design in general. Like... LFR you pretty much ignore all of the mechanics and just pew pew. In Normal you pay attention to some of the mechanics but can ignore some, then in HM you actually have to pay attention to mechanics. That's why it sucked imo. Very few fights added something interesting and dynamic into them.
Hell... I think Morchokk had the potential to be the MOST interesting fight in the instance on hardmode, instead they designed it such that you could just split into two completely independent groups that just ignored the other group with almost no enrage timer... Yay!? Interesting and possibly complex fight turned into: eh, you could really probably just 5 man this on normal and it would be the exact same fight.
"If the world is something you accept rather than interpret, then you're susceptible to the influence of charismatic idiots." -Neil deGrasee Tyson
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