1)
White Magic / Succor actually predates Conjury. If I'm remembering things correctly, Conjury was taught to people by Moogles -after- the destruction of Amdapor.
Both technically borrow aether from nature, but at different strengths. While Conjury is all about communicating with nature to provide balance, Succor is more about using the power of the Elementals to enact their will. (or something) I think Conjury is a little easier on the environment, but I don't know if this is explicitly stated. A good White Mage (like a Padjal) probably has much more ability to calm the forest than a Conjurer. (It helps that Padjal are from families with strong Conjurers. If it weren't for the whole Padjal and the MSQ Hero being the exception, I would imagine the cream of the crop Hearers would be next in line to get Elemental permission to use Succor.)
2)
They're umm...different? I would think at the end of the day, a CNJ and a WHM of otherwise equal ability/power would otherwise be fairly equal. If we set aside gameplay mechanics that were put on A Realm Reborn to enforce the DPS/Healer/Tank roles and instead look at the 1.0 skills when these were not as enforced, the 1.0 Conjurer was actually a pretty good damage dealer. By communing with different elementals and spirits, they had access to fire, ice and lightning spells, on top of their wind, water and earth. White mage was added into 1.0 at a later time, which makes things a little funky.
Y'shtola things:
The fancy protection spell Y'shtola uses so often in cutscenes used to be a CNJ skill in 1.0. It also sorta looks like a SCH sacred soil. Seeing how most of the Scions have abilities that don't quite line up with in-game mechanics, it might be easier to assume they're just special. ...maybe it's something she picked elsewhere.
edit: Sounsyy beat me to things.
White Magic / Succor actually predates Conjury. If I'm remembering things correctly, Conjury was taught to people by Moogles -after- the destruction of Amdapor.
Both technically borrow aether from nature, but at different strengths. While Conjury is all about communicating with nature to provide balance, Succor is more about using the power of the Elementals to enact their will. (or something) I think Conjury is a little easier on the environment, but I don't know if this is explicitly stated. A good White Mage (like a Padjal) probably has much more ability to calm the forest than a Conjurer. (It helps that Padjal are from families with strong Conjurers. If it weren't for the whole Padjal and the MSQ Hero being the exception, I would imagine the cream of the crop Hearers would be next in line to get Elemental permission to use Succor.)
2)
They're umm...different? I would think at the end of the day, a CNJ and a WHM of otherwise equal ability/power would otherwise be fairly equal. If we set aside gameplay mechanics that were put on A Realm Reborn to enforce the DPS/Healer/Tank roles and instead look at the 1.0 skills when these were not as enforced, the 1.0 Conjurer was actually a pretty good damage dealer. By communing with different elementals and spirits, they had access to fire, ice and lightning spells, on top of their wind, water and earth. White mage was added into 1.0 at a later time, which makes things a little funky.
Y'shtola things:
The fancy protection spell Y'shtola uses so often in cutscenes used to be a CNJ skill in 1.0. It also sorta looks like a SCH sacred soil. Seeing how most of the Scions have abilities that don't quite line up with in-game mechanics, it might be easier to assume they're just special. ...maybe it's something she picked elsewhere.
edit: Sounsyy beat me to things.
