Well, if we want to take a look at the Dragoon class quests... Jump is technically rewarded as a class skill for completing the level 30 class quest.
I haven't done that in a while, but reviewing the steps and dialogue (http://xivdb.com/?quest/66603/Eye-of-the-Dragon) shows that... well... all the Main Character does to be acknowledged as a dragoon is that the Eye of Nidhogg that Estinien carries "rouses" for him/her. This seemingly grants "the power of the dragon" to the MC (or rather renders the MC into a "vessel" for it), and from then on Alberic takes it upon himself to impart instruction. It's said that the Eye only "chooses" the "strongest and wisest dragoon" as the Azure Dragoon, yet Alberic doesn't acknowledge the MC as the Azure Dragoon until much, much later. That sounds like, "oh, well, you can be a dragoon now, but you still need training and you don't know how to harness or use that power so you aren't the Azure YET".
I'd say there's definitely some magical component to it that probably comes from exposure to either draconic artifacts or dragons themselves. It certainly SOUNDS like a prerequisite for dragoon techniques, since it's only afterward that Alberic takes on the MC as a student. That said, if you fulfill that prerequisite and you have a mentor capable of instructing you in "jumping", well, there you go. (PLEASE NOTE THAT THIS EXCEPTION OF THE MC'S INDICATES THAT YOU DON'T ACTUALLY NEED TO KILL A DRAGON TO BE A DRAGOON)
As for the explanation (EDIT: as to how jumping actually works)... SHRUG. I'm going to chalk it down to "cuz dragons, bitches" as I've always done.
I haven't done that in a while, but reviewing the steps and dialogue (http://xivdb.com/?quest/66603/Eye-of-the-Dragon) shows that... well... all the Main Character does to be acknowledged as a dragoon is that the Eye of Nidhogg that Estinien carries "rouses" for him/her. This seemingly grants "the power of the dragon" to the MC (or rather renders the MC into a "vessel" for it), and from then on Alberic takes it upon himself to impart instruction. It's said that the Eye only "chooses" the "strongest and wisest dragoon" as the Azure Dragoon, yet Alberic doesn't acknowledge the MC as the Azure Dragoon until much, much later. That sounds like, "oh, well, you can be a dragoon now, but you still need training and you don't know how to harness or use that power so you aren't the Azure YET".
I'd say there's definitely some magical component to it that probably comes from exposure to either draconic artifacts or dragons themselves. It certainly SOUNDS like a prerequisite for dragoon techniques, since it's only afterward that Alberic takes on the MC as a student. That said, if you fulfill that prerequisite and you have a mentor capable of instructing you in "jumping", well, there you go. (PLEASE NOTE THAT THIS EXCEPTION OF THE MC'S INDICATES THAT YOU DON'T ACTUALLY NEED TO KILL A DRAGON TO BE A DRAGOON)
As for the explanation (EDIT: as to how jumping actually works)... SHRUG. I'm going to chalk it down to "cuz dragons, bitches" as I've always done.