well good conclusion Matt. except only its not at all true.
i dont really understand why, its not normal dependent, not always "star shaped" [5faces sharing a point] dependentm
i really dont know why alias did this in V7.0
especially when subD editing is like editing NURBS in maya; u dont edit directly on the surface [like you do with polygons]

here is the pic u posted. the suraces hihglighted are the same exact mesh, only 2 extra edges. the 2 faces in the middle are fine

i really dislike this.