Would you like an in-game parser?

[Reynhart]

Read my post again.

Unless the first part of your post is for me too, the "slacking" part is the answer you gave to me.

Why you nitpick thats okay everybody can see when a tank or a healer is failing to do its job?

Do you see exatcly how much damage the tank took ? Do you see exactly how much healing everyone received ? Do you see how overheal everyone received ?
Having a parser does not show if the DPS are failing to do their job. If your party does not meet the DPS checks, you'll realize very soon. What the parser can show, and why I don't really like them, is how above the DPS are succeeded, and how that "above" can be not enough for some.

Since you're a healer, let me ask you this. You're in a 8-man party. The fights goes with no death, but, in the end, you realize the other healer healed for a noticeable amount below you. Would you say that he failed at his job ?

How could my group of 7 people kill sephirot 2 min faster than a 4 dps group? And we are in the same gear, I'm waiting for you to explain.

Better knowledge of the fight, better coordination with people you're used to raid with, jobs not optimized for the raid, and yes, gap in player skill.
But, among all that, I should also say...why does it matter ? Didn't they kill it too ?