“Apparently that “natural-born” clause has become pretty elastic, with some grave misunderstanding of just exactly what it means.”
The Naturalization Act of 1790 defines “natural-born” precisely — children born of citizen parents (plural).
And it explicitly states that if a child has a foreign father, he cannot be a citizen, let alone a "natural" citizen.
A Foreign father prevents American citizenship according to the Naturalization act of 1790. Are you sure you want to let that act of man define "natural" citizenship?