As the title suggests, LFR N'zoth is the raid killer this time around. First you have to spend 5 minutes kicking everyone who doesn't have the cloak, since it's a REQUIREMENT for this part of the raid. Then you have to spend another 10 minutes kicking the new people who joined without cloaks and then explaining the mechanics of the various phases...then immediately wipe because people aren't clicking on their bodies at the end of p1, or aren't replenishing their sanity when they emerge.
The LFR I was just in wiped 17 times before I decided to call it quits, and they BARELY got N'zoth down to 90% the second time he was vulnerable. After that half the raid almost immediately died due to various mechanics that they weren't paying attention to.
4-5 people left after each wipe, which kicked off the whole "kick those without cloaks and explain the raid" thing every time. I spent 3 hours on that one boss that--while difficult--should not be so impossible for LFR.
I fully expect that Blizz will either block people from queueing if they don't have the cloak or reduce the sanity drain of various abilities as well as possibly reducing the health of N'zoth and/or Psychus by the time next week rolls around. It's simply nigh impossible to do with a random group as it stands.