Here's the thing about burst: There's no need to give every tank the same mechanic just to achieve burst potential.
Burst just means you're able to cram a lot of damage into a small buff window. How you get to that damage doesn't have to be the same across all jobs at all.

PLD:
Avenging Wrath (uh, get the reference?): Upgrades from Fight or Flight via a trait. Increases your damage done by 20% for X seconds and enables to use of Confiteor. XY% of the damage you deal is added to your next Confiteor. Casting Confiteor downgrades the effect to Fight or Flight.

With this, Confiteor becomes this ungodly huge and satisfying nuke you drop when the burst window is just about to close. You can balance the total damage you do during Avenging Wrath to be around equal to WAR's IR window, yet both jobs would be achieving that damage in different ways.