Sadly, I think it is not, the amount of gil you put in leveling it up would never be enough to cover what you can sell out of it.

Am I the only person here, that thinks it is really a waste of resources if you continue to think that someday all those gils wasted in leveling up your gathering class and crafting class would one day pay off?

I became a goldsmith in the hope of gaining some gils to buy things for myself, but my god... the horror that faced me in leveling up that class... in the end I stuck with it not for making gils, but actually for sheer boredom when one is at the post story life in the game.

I make more money killing mobs for their drops actually...