Are my mitigation numbers off ?

[Reynhart]

Shield presence
Effective tankbuster mitigation
Fluff mitigation
Group composition collaborated mitigation
Tankbuster mitigation amount performed in succession (T13 for example)
Mitigation in a short timeframe

Shield presence is not very high when it comes to average mitigation.
For tankbuster mitigation, you need frequent mitigation, duration is mostly irrelevant. And Inner Beast still has the shortest cooldown.

You can also mention I didn't include fight duration, since, if the fight is shorter, the tank and the raid will take less damage overall, and self healing skills.
As for group collabored mitigation, it really doesn't depend on the tank, so there's no reason it should affect their relative numbers.

But, even with all this, PLD is far from being the king of mitigation. And is, in fact, absolutely not, in several content.
If you look at the other side of the spectrum, WAR (and DRK) DPS is undoubtedly higher that PLD.

And it's even before we discuss if this mitigation is even useful...