For the non-WHMs out there that may be confused, I'd like to clarify that Baramnesra is not Amnesia-na. It's a bar-status spell, not a cure for the status. Which means that (assuming it works the same as the other bar-status spells) it's going to be nothing short of completely worthless.
The bar-status spells in the game do not increase your chance to resist the spell (or if they do, then even with a ludicrous amount of enhancing magic, the effect is not noticeable), they only seem to reduce the duration of the effect. And I can tell you that even then, the amount it reduces the duration (again, even with ludicrous enhancing magic skill), seems barely noticeable. We were even testing it in Dynamis Bastok one day, using barpetra... basically what we found was that sometimes, some of the members of the party with barpetra occasionally became un-petrifed about half a second sooner than the members of a party without it.
So yeah, don't expect to exact any kind of revenge on imps based on the availability of this new spell. If it's anything like the others, its effects (or lack thereof) are going to be laughable.
The only advantage it has at all, is that because the Amnesia effect is not removable by any other means (other than the Ecphoria Ring, which apparently doesn't always work), having this spell effect active is better than nothing at all. But not by much.