Nerfing a tank's ability to self-heal would cripple the role. A selfsustaining tank is a huge factor in a lot of scenarios, enabling healers to vary their roles, and dps to really cut loose. Cutting the effect of Equilibrium, Bloodbath, Thrill of Battle, Inner Beast, and even Souleater would force healers to only focus on the tanks. Even Dark Knight's Blood Weapon and Syphon Strike will be affected.
I've read a lot of threads about the dps, but tanks use this dps to sustain their abilities, and it's what gives each its distinction.