Would you like an in-game parser?

[Taika]

I have yet to see anyone seriously consider that if a lot of people had struggled to do what they find basic, maybe that thing isn't all that basic after all.

But what is described here as "basic" is the baseline set by the content itself through DPS checks. If you're unable to perform your opener and basic rotation in a dummy situation (which 1st phase of Zurvan is), you won't have enough DPS to clear the fight - or even the fight's SSS doll probably. If you're not on this level, you have no business in this content (since you're simply making others to carry your weight), and need to practice more before participating. And the fact doesn't change no matter how many players are below this level.