I don't see any contradiction in Hindraker's thesis, at all. He saying that she's mounting a campaign for president, and at the same time she has created a flawed foundation from which to launch that campaign. At least, that's his premise or theme of his piece.
You're last question "then why would she do it to run for president?", is intimated in Hindraker's thesis. That's the question he's asking, "Why would a person with presidential aspirations quit the only job that, if successfully completed would lend them credibility upon which to launch their campaign?" It's a good question.
The “faulty foundation” is that of those who say Palin resigned to run for President and say “what a stupid move for anyone wanting to run for President!” What has she said or done to indicate that she resigned to run for President? NOTHING. They are throwing darts in the dark and claiming to have hit the bullseye. In reality, they don’t have a friggin’ clue.