Though I see your point, the simple fact is there is less required of you for the majority of the fights/trash in Cata Heroics. Nearly all the pulls in BC required heavy CC, cool downs, interrupts, etc... as a healer, you would likely have to drink after every trash pull. It would take that much mana to sustain your group, and back then, you could cast lower ranked spells to conserve mana. It wasn't unheard of for a hunter to chain trap or kite a mob around when things got crazy. You couldn't just AOE the whole group. Now days there are a few gimmic trash pulls, but for the most part, you just aoe or single them down if there's only a couple...you don't HAVE to interrupt, CC, or anything of the sort.

Not every single pull was like this, and if you were one of the few people who raided heavily and had good gear, I'm sure things weren't this challenging. But it took a lot more time to get gear, and unless you raided or had hours to spend grinding mats for a crafted piece of gear, you were in blues and greens. After some time, I had a group of friends that I ran dungeons with on a regular basis, and though we had developed a rhythm, things could still go wrong and we would wipe.

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