Another thing that many tanks learn for the first time during the Ifrit fight: if there are adds during a boss fight, many times it's not the tank's job to deal with them. In Ifrit in particular, the tank should not attack the nail because the DDs will get caught by Ifrit's fire breath.
Also, if the healer Rescues you to a different position because you're cleaving the party, please don't go back to what you were doing that was cleaving the party.