4Gamer Interview with Yoshi-P!

[Zojha]

Personally, I still wish they'd expand on that idea and give us more dual-job classes like Arcanist.

And I just wonder why, because the only thing you "gain" compared to having it as separate classes is the fact that if you someday want to switch, you need to level one less class. That aside, it's only hinders your freedom of playing all classes even more because you need to buy hymns in addition to gathering the gear.