Not trying to be a dick here but you do know this goes both ways, right? Not everyone is going to know the fight or watch a video to learn it. You need to be ready for that. If you know the fight and don't want to say something, then YOU ARE PART OF THE PROBLEM TOO.
Let's take it one step further. People always scream how stupid and shitty the populace in WoW is, yet they are doing the same thing you are-- giving NO help or direction to those who obviously could use it. I would be willing to bet that 90% of the people in LFR WANT to do a good job yet people get kicked if they ask questions in LFR and LFD. Instead of people going "Okay, new guy, here's how it works" and working together to be successful, most new people are told shit like "LRN2PLAY NUB". No one offers any advice or tips, and everybody wipes. THen the same people who are like "OMFG NOOBS" bitch because the fight failed. Raiding, even in LFR, does require SOME coordination. This mentality of "Let's just call people stupid!" in LFR doesn't do shit for anybody except make a bunch of nerds feel superior over someone that's new. I come from the fighting game community as a tournament organizer, and let me tell you THAT attitude is fucking BULLSHIT. It's been a blight on the fighting game community and it has turned away so many eager players because some people just want to be dick heads because they think they're better at something than someone else. Seeing it in WoW ENRAGES me.
Here's an idea; If no one is stepping up to give direction to the raid, and you know the fight, then YOU step up. People don't want to go into any situation and fail. If they need some guidance, offer it. If they don't take it, it is what it is. But think about how many people want to be better, and no one is stepping up to help. It still leads to the same place, people failing and raids wiping.
WoW's community is shrinking, and will probably continue to shrink until there's nothing left but a bunch of assholes who scream "LRN2PLAY NUB". Be someone that's going to help make a change rather than getting on here to talk about how stupid people are and maybe the WoW community will get better.