I will strongly disagree with this.
When I first stepped into BC Heroics (H Slave Pens FTW - largely considered the easiest heroic in BC days) - I remember my Paladin tank getting one shot by the first pack of mobs - and he was in full blue lvl 70 gear. The normal --> heroic transition required an entirely new healing mindset (go big or go home) and perfect timing on everything ... every single pull. Then you had to farm the crap out of the few bosses you could kill (once per day) so you could move on to the next instance. There was no "skipping around". Karazhan (10 man raid) was easier than the heroics were
Fast forward to WotLK Heroics. Umm... the gimmicks made things interesting, but the it allowed for a lot of sloppy play, because they mobs didn't hit nearly as hard. You could pick almost any Wrath Heroic and be successful with a little practice.
Wrath was easy mode compared to BC. A step up in difficultly would be nice.
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