For every 5-10% of elemental melee you have that is equivalent to that production's success by 1%. The charms give 5% more success to that production, so the answer is yes.
Why are people using charms instead of secret production book?
Secret production book's description is: Production success rate +15% Production loss rate +80% If Alchemist, production success rate +4%, but according to iruna-online.info, it gives great success.
CC: Kijimu Party May I know the basis for your claim on this?
They use the charms for recipes that don't have a great success make, or for strengthening items. This is precisely because of the loss rate in the Secret Production Book. You will be losing your mats 80% of the time, which is bad. I use SPB each time there is a great success for a weapon (e.g Fudo Myoo Sword) or for an item (Fancy Pet Food x3 in one make instead of just 1). My claim is that I have found that I have gotten more great success makes with a SPB than I would have with a charm. In 20 World Tree Bow makes with the SCP I have managed to get 3 Yggdrasil Bows whereas with a charm I have gotten nothing. Maybe I'll post an informative video on this to show how it works.
Former GM of Sharpness and Iridescence, Lv.83/44 Before Resignation. Characters Level 373 Alchemist - MUCC (wh5em8) Level 359 Paladin - 恒雄 Level 311 Servant - Cariosus Level 295 High Wizard - Anger Level 146 Sniper - Archmæis JP VER Level 261 High Wizard - KHH12 (Safe-Haven)