Perhaps the blog excerpted too little of the petition (it started at page 55, or PDF page 63). I recommend starting at section V.C on page 52, or PDF page 60 instead. I think the description of Comcast’s actions since 2009 paints a pretty damning picture of Comcast’s abuse of its monopoly on high-speed last-mile wire in many parts of the US.
Or, read the entire petition, which is a good read; it’s 100 double-spaced pages. The PDF also includes other evidence: 22 pages of statement from Ken Florance, VP of Content Delivery (PDF page 110) and 100 pages from economist David Evans (PDF page 134).