Honestly, I've got no idea what *you're* talking about and bringing up the comparison with a single tank that you already know that you can regularly pull off of because you outgear him doesn't really say much. While in Shield Oath, using a relic weapon and a mix of AK and DL gear, I've pulled threat off of a full DK PLD with relic +1. While it's pretty hard to screw up RoH, it's pretty obvious that a lot of people end up doing just that, whether by not using FoF, CoS, and SW like they should be or leaving gaps in between attacks rather than queueing up a new attack right before the reset timer finishes.
I've pulled off of WARs in better gear on my PLD and pulled off of PLDs in better gear on my WAR. I've done the same when I'm playing the same class as the other tank. I've had to restrain myself when running with pretty much every tank I've ever paired up with because I know exactly how to maximize my damage and enmity generation and a lot of people *don't*, even when they're supposedly amazing tanks that have never had enmity problems before (and, yes, I've run with FCs that say that their tank's enmity is amazing only to find out that they get completely bowled over by me).
Using your single data point means absolutely nothing. Half of the PLD DPS parses that I've seen mean nothing either because there are a *lot* of PLDs that are completely and utterly incompetent yet still progress because doing the absolute minimum to progress while playing a PLD is remarkably simple. When parses start existing that don't suck massively and we start collecting data points from similar skilled and geared PLDs and WARs, the question of practice v. theory will be answered but, having played both a prolific amount with numerous other tanks and solo as well, I haven't noticed *any* kind of evidence that suggests appreciable deviation from the theory, assuming that the PLD isn't just facerolling their way to victory.