although i agree that who ever has intial hate is the mt the fight long barring them dying.
that being said sometimes provoke has a place as if your ot you have no way of knowing if you are 2nd or 3rd on the list so popping provoke and waiting a sec before continuing your attacks will put you 2nd leaving the mt as the mt. this will ensure that if the mt dies the boss will auto switch to you instead of chasing some random person.
admittedly chances are youll be 2nd or 3rd on the list anyways but you never can quite tell.
as for any 2 tank raid scenario you wont be fighting over hate at all and youll only use provoke on intended tank swaps or if mt dies.