Just be aware that, as hard as it might be for forum-readers like us to imagine, there ARE plenty of folks in-game who simply have no idea that these resources exist. Not every FFXIV player reads the forums, or even knows that there are videos you can watch online. Not everyone that plays an MMO is also Internet-savvy. A lot of folks who come into an instance and ask, "What do I do?" either honestly don't understand that there's even another way - or believes that getting the skinny straight from other players is the best way to learn.
There's a case for that, given that a lot of internet resources have conflicting and alternate strategies - it's good to know which strategy is currently "in", and that your party will be doing. For example, I first defeated Ifrit Ex long after it was worthwhile to have him on "farm" mode. The guide I'd read suggested that the tanks both stand at the edge of the arena, with enough gap between them that Ifrit won't hit the off-tank with Incinerate. The tanks pretty much never move except to reposition for the next set of Radiant Plumes; Vulcan Burst doesn't knock them back because they're already at the edge of the arena, and when swapping hate Ifrit simply turns to face the other tank, rather than either tank having to move (and potentially getting both tanks hosed down with Incinerate while they reposition).
This was the method that was used on my first win, and it works great. However, no tank I've encountered since uses that strategy. They all stand with Ifrit pointed straight outwards, and expect the off-tank to move to Ifrit's side, and run in when the swap occurs. It works, certainly, but is much messier - and, since I wasn't expecting it, I wound up getting hit by every Incinerate until I figured out what was going on.
So, there's value to be had in asking the group with for advice if you're inexperienced, even if you've done research ahead of time. I don't mean to imply from this that you SHOULDN'T use guides - just that it never hurts to confirm what you've read with the players you're with when trying out new content.