None of the primals are really about lag as much as people want to complain that it is. They are about not doing them with terrible pick up groups.

Ifrit: DPSes just can't understand the concept of quickly killing a nail.
Titan: Stop falling of the ledge mages.
Garuda: Well. Too many different things for weak-minded pick up groups to pay attention to.

Garuda is the worst, if you're stuck with Duty Finder groups, then the best advice is to not get frustrated with the wipes. On my third try, I finally got a competent party. I don't mind if they fail a few times, but they're great when they can learn from their mistakes.