OK, sorry if this has been posted somewhere else, but does anyone know how Provoke works?

As far as I can tell, it puts you at the top of your party's aggro "list" (I know it doesn't work outside of dungeons, like in Fates for example), just above whoever was at the top before you cast it, but if you don't do anything to follow up (like a shield or axe throw) you're likely to lose aggro since whoever was at the top of the list is likely to keep gaining aggro.

But...how does it work, really? I don't have much experience using it, but from conversations with tanks and watching them try to switch off aggro during Turn 2, it doesn't work exactly like I described above. Or is that how it works and something is just going wrong or being overlooked/missed?