Yeah, I think I posted ambiguously, what I meant was "because you can AoE zugzug through some instances (like SHH Heroic), people think an instance where you can't* do that (like Blood Furnace) is suddenly super hard".
*to a point.
There is no one answer here.
It will depend on your group composition, gearing and level of play.
There is certain individual mobs in certain dungeons that can easily wipe the party, but on the whole it might be easier overall.
But there is a consistent theme, Hellfire mobs tend to do the most melee damage bar some of the coilfang giant's, ohb has a tough final boss with limited cc opportunity, mana tombs has lots of nasty casters, arc has a tough final quest if you need to keep millhouse alive but is otherwise not too bad.
So in short, they can all be hard or easy, depending on multiple factors at any given time.
Did "Headed South" the second week of Cataclysm, Aye probably the most brutal dungeon experience I've ever had in WoW.
Also the most fun, by a long shot.
They also one and all got significantly nerfed rather than overgeared because the forums were an endless complaint stream about people unable to complete heroics in their pleb pug groups.
blood furnance is literally the only dungeon which requires cc. With current equipment available you cannot tank the packs in the gauntlet. This circumstance makes it not super hard, but harder than any other dungeon. Any other dungeon is clearable without a single cc/slow/snare.
Exactly. The lead-up to the Ogre requires overgearing or patience, and PuGs would fail on this so easy it hurts. Especially with the stealth mobs stunning a non-tank target when they destealthed.
*I* personally rarely had problems with this instance because as a warlock i can single-handedly eliminate/CC three of the mobs from each pull (Banish a demon, enslave the shiva and use it to dps the tank target and/or get it killed by having it tank something, fear a mob). If the party is patient and willing to pull back into the previous room, i can make it 4 pretty easily (Curse of Exhaustion on two mobs, fear juggling them as they waddle back), reducing it to a 2 pull. If we have a mage, as well, its a one-pull and is basically faceroll.
But in a group without an on the ball warlock, that room will murder PuGs and cause group breakups. The rest of the instance is piss easy though, except for sometimes having to educuate (in small, simple words) people on how Murmur works.