The burden should be on those challenging otherwise eligible candidates to demonstrate through clear and convincing historical evidence and legal argument why such persons should be disqualified. "..... because I want it to be that way; that works for me." Birthers are not nuts, and Obama is not NBC, that is why all the pettifogging, lying, and concealment.
Occam's Razor.
Read the article to understand why he concludes that. This isn't just an internet "commentator", he's a highly respected lawyer. There's a lot of research and quote attribution, good discussion, etc. He also goes out of his way to say those who disagree aren't nuts, and clearly says the term "birther" was made up as a pejorative term.
Try reading it instead of criticizing first.