If you thought he was crazed (or hard) before, check out this screenshot.
Also, there appears to be a bug with Kel’Thuzad that he freezes when he’s supposed to summon adds, so I’d be wary about doing Naxx until you see a fix notice.
Runeforge Gossip
A Death Knight's perspective on raiding, guild-membering, and other World of Warcraft activities.
That happened to us, too, on 10 man. We decided it would be easier to do hard mode! We had everybody run behind the tank so that the bomb bots would explode without damaging anybody. Because we were planning on hard mode, we could ignore the tiny bots that heal him.
We did the same thing, and were also planning on doing hardmode anyways.