All tanks should contribute the same damage with Crit/DH being and player skill level. Tanks all bring virtually the same thing so I don't see the point in the large disparity in DPS between tanks that was experienced this expansion. ShB was the best balance of tanks, and that should be the bare minimum gold standard of balancing among tanks. The self-sustain is negligible at best in the content that matters, and in dungeons, the self-sustain determines how lazy the healer gets to be, but makes no difference long term.