Ifrit isn't a gear check. Your dps need good weapons (darklight, GC weapons) and having a mage to LB the nails is nice but not necessary.

If you should end up in a group without a blm or smn, set a dragoon or monk to lb a specific nail, let everyone know which nail that is, and then have everyone else start on a different nail, move to a third nail, and lb will be ready again for fourth nail.

"We'll call the tail nail 12. Polly Arm, LB 12, everyone else go to 3, and then 6, and then LB 9 as soon as you're on it"

It also helps to have the off-tank switch targets too, every bit of dps matters during nail phase if you don't have mage LB.