EVERY character, who is venturing into the wilds, should, and probably would have some knowledge of alchemy.. Its common sense...How would one take care of oneself when out in the wilderness, and out of reach of aid? Its simply ignorant to assume anyone would venture out, without all the necessary skills..
That said, i dont see anyone pointing out that, in time when women did all the cooking/cleaning, that men know how to gather herbs, and cook there own soups, stems, meat, fish, bread, etc.! No.. You consider it a necessiy, that all characters in the game know how to use.. I argue, that all classes need/rely on alchemy, and wouldnt be stupid enough to venute into Labrynthian, without knwoing how to boil up a potion!
Edit: Enchanting IS magic based skill, and you are indeed folding your magical powers into the metal.. Think Dragon Age... Your basically casting a spell onto a weapon.. Youd have to know magic, to place magic into it...The actual definition of "Enchant"im willing t bet isbased on some sort of sorcery, or soemthing similar..
Alchemy, also was primarily used by doctors, or witches.. Practicing magic, or medicine are those who would have been using alchemy.. If were going to be getting technical.