Naxxramas used to be the ultimate raiding experience.
40 people, top of the range computers to counteract the lag, split second timing, zero mistakes... if you weren't the most coordinated team, you weren't capable of doing it.
A few days ago, I joined an 8man PuG, supposedly to do Achievements.
We ended up failing (some people *really* can't handle Heigan or Thaddius), but a few of us continued on anyway. Someone DCed, someone left...
...and 6 of us ended up doing the entire of the Naxx military wing with no healer class.
No, not even a pally or druid tank - both tanks were warriors.
It's a little sad, killing the 4 horsemen without a healer. That encounter used to take 4 tanks and some epic timed swapping.
Then again... I suppose it's even sadder that we didn't manage to get any Achievements done with all 85s except Spore Loser, because someone (different!) failed each time. Seriously... who fails at Thaddius charges with only 7 people, Heigan dancing *before* the second phase, and controlling DPS on the 4 Horsemen?!