[Non-Sequitur]

The pertinent part is underlined. The Founders wrote themselves a "grandfather clause" so that they would be eligible to run for President since their parents were foreign born.

Right. Now where does it define 'natural born citizen'?

[DJ MacWoW]

The Founders wrote themselves a "grandfather clause" so that they would be eligible to run for President since their parents were foreign born.

Read the above sentence again. One or more of their parents were foreign born which made them ineligible to run for President even though THEY were born on American soil. Their parents birthplace made them ineligible without tis clause :No person except a natural born citizen, or a citizen of the United States at the time of the adoption of this Constitution,