The statutes impose conditions which must be met and authorizes Consular officers to deny the civil rights of citizenship until and unless those evidentiary and residence requirements are met. Since the civil rights are not forthcoming from the political community until and unless the conditions are satisfied, no current and future enjoyment of those civil rights in the political community will occur. Therefore, by definition, no vesting of those civil rights has occurred.
Assume that you have all the evidence, that it is credible and reliable, that you are not a government official, and that the person has not submitted to government examination. What do you find as to citizenship? I would find statutory citizenship based on 1401(g), upon finding citizenship and residence of the US citizen parent. Kabar would say that citizenship didn't attach yet, because the person hadn't submitted evidence and requested a grant of citizenship.
If I may paraphrase, I think I agree with what you say there. It doesn't get to the nub of the debate though.
If the conditions of the statute aren't met, the person isn't a citizen. If an examiner finds the conditions aren't met, he will find that the person is not a citizen. If the examiner finds the conditions are met, he will find that the person is a citizen.
The argument I had with kabar is different. It has to do with WHEN and IF citizenship vested, assuming the condisions are met. Is citizenship vested when the conditions are met (which is a circumstance of birth, and I say happens at the instant of birth), or is citizenship absent until the evidence is examined by the government, which will be later than the moment of birth, if it happens at all.