Would you like an in-game parser?

[Zeonsilt]

If people are putting up Susano parties with a minimum requirement of i340, they’re dumb. I’m sorry, not going to sugarcoat that.

Haven't seen any of those, though.
Pretty much all parties locked at 330 or 335 these days(Chaos DT).
It is indeed dumb to make it "340 only", but "330" is pretty "meh" at this point, it's already December. Even Ivalice was released in October.

All that being said, I’ve seen people in full 320 do a far better job than someone in 340 DPS-wise, so the ilevel requirement for “better DPS” or for “things to die faster” isn’t exactly going to give people what they want when they set ilvls so high.

It's impossible to know about that until the actual combat part starts (and only if you parse). Unless you know them personally or that person got some FF logs available on another class.
I've seen a lot of those too.

Imagine you got a full 320 party, you will not know who underperform in that one and the only way to know that is "to parse".
Otherwise, it's "ggthxbye" and time to create another PF with different people. That's why people like to play it "safe".

p.s. Not too many people parse in FF XIV, especially when it's "PC exclusive" feature.