I prefer to go in blind and that's why I'll go in first thing when a new patch drops. Usually as dps. If friends are on first thing I'll go in with them, but if not I'll dive in by myself. But sometimes not everyone can be on first thing and we'll plan a blind FC run in the evening the same day a patch drops. That's for brand new content. But if it's something that's been out a while but I've not bothered to do it yet, like an extreme fight, I'll review a video just to get some of the basics of the encounter down. I won't remember it much as I learn best by doing, but at least when I see something in the fight it'll jog my memory of "oh yea the video said this was coming and how it should be handled".