Typical foray into an EX trial for me goes something like this:

Beginning stage - Totem count 0-5: Study a guide extensively, fail all mechanics anyway. Very likely will wipe the raid.
Intermediate stage - Totem count 6-10: Understand most mechanics at this point, but still cleaning up. Less likely to wipe raid, but still a high possibility.
Damage Dorito stage - Totem count 11+: At this point, I am capable of teaching the fight to others as I have a full understanding of all the mechanics. I can still make mistakes, but am more likely to die to someone else's error. I will also allow myself to start rolling for any dropped mounts at this point. I don't roll on mounts during the learning/clean up stages.

Guides helped my awareness level of the mechanics. But I need to participate in the encounter in order to break it down. I will never learn an unknown mechanic through a guide, or by being told where to go. I would much rather rely on my own reaction to the mechanic, than someone else's. This helps to ensure that I still don't get clipped by the damage anyway.

In short, the guides aren't needed. The majority of the learning takes place inside the encounter regardless.