>>2013200
>Does LUK also improve the chance to not degrade when refining
only on your character
>Can you even refine up to +S with a blacksmith? Or is a blacksmith character mandatory?

Make a 255 LUK refiner, just need 1 skill point on refining. You can brute force with the help of pity system. Buy 4 stacks of mithril ore and you're good to go.