I find this to be an extremely amusing comment, given that it's coming from someone who's profile says they main Warrior, and half of Warrior's defensive kit is based on active mitigation.
Actively mitigating dmg means self-healing. Bloodbath, Equilibrium, Thrill of War, and Storms Path are all used to actively mitigate via self-healing. Further, all of those moves can be coupled with other moves to increase self-healing dramatically (Ie: Bloodbath + Vengeance/Berserk/Deliverance + Fell Cleave or Decimate... etc) If you're using any of these when you don't need Hp, then you're wasting them, but according to this comment that's totally fine, given that Tanks are, apparently, not supposed to heal dmg after the fact. That's the healer's job. So, really, War's Defensive CD's consist only of Fracture, Vengeance, and Holmgang, because using anything that self-heals can be safely ignored since it's not their job ...
It's also totally okay for Pld's to drop their Dps to zero and spam cast Stoneskin (but not clemency, because self-healing after the fact is not the tank's job). It doesn't matter that their enmity generation will collapse to the floor. It also doesn't matter that the current Tank meta involves heavy Dps checks. Stoneskin and flash is where it's at. That's the bee's knees of Tanking right there. Being able to consistently apply RoH's Str down debuff on the boss is a non-issue, and keeping GB's DoT up for maximum Dps is totally not important. Pld auto attack can handle all of that lost potency cuz it's just that fast (obviously this is all sarcasm).
Seriously, I don't even understand where these kinds of comments can come from. At least their good for a chuckle, I guess.