About new overmeld

Today I noticed change for overmeld this when I overmeld for craft gear.
http://https://img.finalfantasyxiv.com/t/44fc093d851594d701d09c855c13e05605af3f95_43.png
http://https://img.finalfantasyxiv.c...5af3f95_43.png

I dont sure it's good use click it ON like less spam-clicks, yeah?

Was worried if I click ON and all materias lost when fail

You don't lose all of them when you fail. Basically that just tries to meld over and over automatically until it succeeds. It only uses as many materia as it needs to. No different than doing it all yourself. Just fewer clicks.