See... you're rewriting the protocol. It's all together possible that that part of the code is off limits to the person putting in the items to be crafted.
How is that rewriting the 'protocol' ?
Neither of us know how the API works, but I would think crafting would basically have a table of types (as keys) with the requirements for each object then each object could return a creator function.
As for being 'allowed' this is not a class III medical device, its just a game. They are allowed to do what they want. I don't think fletching has to be much different from ammunition creating in FONV. But there I go again, comparing Skyrim to a finished project.
/me ducks...