There was a Ghostcrawler post recently that outlined, in proper detail, the logic behind capping Hybrid DPS just below that of a pure DPS class.
Tonight, we got Tribute to Mad Skill after wiping only once on Anub'arak, through nothing more than bad luck.
We almost wiped the second time because our main-and-off-tank-encounter-breaking-Paladin-healer died at around 7%.
We survived because both of our hybrid DPS -- Chayah and I -- switched to spam healing the tanks to keep them alive, with occasional support on Pen Cold healing so that our Discipline priest could provide Penance etc. Once our Anub tank had been stabilised after a Frost Slash that triggered her Ardent Defender, I switched back into Shadowform and continued to support nuking Anub'arak.
49 Attempts. Mad Skill. Cause? Hybrids.
That is why we are taxed. Accept it.
And we both still did over 5k DPS.