I too would like some solid information on crafting. I've seen sites that have certain things like cloth robes and glasses listed as magical craftsmanship being the preferred type, and then iron barbuts and solerrets being craftsmanship, though nothing gives an idea of a set value like what Estellios said up above (as in, barbut requires 85 craftsmanship, etc). I can wrap my head around that, but I don't know which is which because it's not actually listed anywhere "official", it's always from some 3rd party website that has a "general idea" about what they're talking about or going on a single person's parsed results from far too little testing. I remember some "general ideas" from FFXI taking the direction you were facing into account depending on what element the synthesis was, and I never saw anything to back any of that up. Hell when I broke down and tried it I remember having worse results. I dunno, I might not have looked hard enough or tested enough, but unsubstantial theories were never enough to win me over.