This is actually something I touch on in my thread:
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, But yes I have always believed that he specifically gave nagato the rinnegan so that he could unlock it. Why else would he give such a precious item to some weak kid in one of the deadliest countries in the world with no protection, he had no choice, he had to give it to him.
Your reasons for believing so seem kinda of lacking though, I mean 3 paragraphs on gramatical wording? keep in mind that these are merely translations of a diferent language that could easily mean something else in its original form.