Why Warlords Bloodlust is better than Fervor of Battle.

I was playing and took the keystone warlords. I was debating weather fervor would have been better because of how often i double hit with my passive and use abilities, however after this play i have come to the conclusion that warlords is my lord and savior and ill (almost) always take it over fervor.

You cant see my hp in this recording because i clicked the jax, but i got put down to 9 hp first, then chunked back down to 6 hp in that 1v2.