I read this article in Nature (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10768.html) as it describes two circumbinary planets. If it is assumed that most stars have a planet orbiting it and most Binary Star systems are elliptical, then wouldn't the majority of Binary Stars system not have planets due to tidal forces of both stars? I am assuming the orbital path of the stars to be intersecting in a figure "eight" pattern (e.g. the last animation of barycentric coordinates on http://en.wikipedia.org/wiki/Barycentric_coordinates_(astronomy)). Thanks in advance.