@Australopithecus:
That indigo line does not work as a link(assuming that’s what it is). So this is just a claim without any premise corroborating it.
http://www.mangapanda.com/one-piece/664/14
That's really the only evidence we need. Oda indirectly confirms that Monet is a byproduct of Law's ability through Usopp.
Your theories are well-written and all, but alas, we do have word of God backing up Law's operation.
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@Australopithecus:
Well, they are not ‘fan-made’. That’s for sure. I kind of fail to understand what you mean by ‘unofficial’. If official means it is directly coloured by the author, then yes, they’re not coloured by the author, but they must be approved by the author himself, and he most likely gives his opinion on how things have to be. Otherwise, it would be an infringement of copyright, which is not.
Many characters have color schemes that are completely different from Oda's official ones, like Jora having green hair when she actually has yellow-orange hair.
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@Australopithecus:
Besides, and this is the more important issue here, why in the world would that part of the story be dedicated to telling us about defective Smiles if they will not play any role in the future events of the story? That’s just a waste of panels that is untypical of a professional writer as Oda-sensei.
You're looking too much into a scene that was just to showcase the Dwarves struggling and having the product of their slave work being deemed useless.
Those "incomplete" SMILEs are not even actual SMILEs. They probably don't give powers.
This is supported by the line "Those haven't completely turned into SMILEs yet!", which means that there's no such thing as an incomplete SMILE.
@Australopithecus:
So she came to Law and told him to operate on her by completely removing her totally functional arms and feet permanently, throwing them in the garbage bin to decompose, and replacing them with those of birds because she desires to scout the island.
Do you really believe this scenario? I don’t.
Dude, she was willing to kill herself to protect Caesar.
She is willing to do sacrifices in order to do her job, so yes, it's a believable scenario.
And why do you talk like she lost a lot by discarding her limbs? If anything, she adapted very well to them, being able to write and read with her wings. If she was a SMILE user, why didn't she turn off her animal parts to do those things?
After all, according to you, she can turn on and off her "abdomen feathers" (which, honestly, looks like just a fancy skirt to me. That skirt is not part of her tail either as her tail's feathers are huge and can be seen below her), yet she is never seen turning off her bird limbs.
By the way, you gotta remember that Den Den Mushi do not work on the cold, so it makes sense for her to wear a fluffy skirt to keep the Den Den Mushi warm. This explains why the feather skirt was discarded once Monet returned from her scouting.
With so many inconsistencies in your theory, I will just go with Usopp here. Nothing you pointed makes any more sense than Law just operating her, which was actually indirectly stated by Oda himself through Usopp.