Just make it apply on use already (and apply to the PLD) ... when Divine Veil was the only Tank shield it made some sense for it to be 'special', but now that the other Tanks all have an instant shield / party mitigation the heal requirement is simply antiquated and clunky.

Either that or have the heal apply part of its potency to the shield, so at least there would be a reason for the heal requirement (though that may be verging on spread crit-lo territory)