The document you posted basically refutes what you are claiming.
Nowhere does it mention the idea that NBC = 2 citizen parents + born in the nation. Accordign to document: The mother is basically ignored and has no relevance to child’s status, the place of birth is overwritten by the father’s status, and Natural Born Citizenship is never mentioned.
Try this one
This definition was entered into the Congressional record of the House on March 9, 1866, in comments made by Rep. John Bingham on the Civil Rights Act of 1866, which was the precursor to the Fourteenth Amendment.
(center column, 2nd paragraph)
“[I] find no fault with the introductory clause, which is simply declaratory of what is written in the Constitution, that every human being born within the jurisdiction of the United States of parents not owing allegiance to any foreign sovereignty is, in the language of your Constitution itself, a natural born citizen . . . ” John A. Bingham, March 9, 1866 Cong. Globe, 39th, 1st Sess., (1866) [page 1291]
(http://memory.loc.gov/cgi-bin/ampage?collId=llcg&fileName=071/llcg071.db&recNum=332)
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Note the usage of the singular 'every human being' in conjunction with the plural 'parents'.