Nice idea you have there but I stopped dead when I read the preservation stone stuff. If you have the time to read the item description, you'll notice that it doesn't say "additional success rate". FYI, the preservation stone only preserves your item when forging failed. There are no more additional function mentioned in the item description. Furthermore, no game will ever disclose the exact rates on their server (unless the game is a private server. ). Why? There are many factors behind it like revenue, player base, customer satisfaction, COMPANY POLICY, etc.