Have you seen the video Veloduo? Mcewen was coming from 3rd of 4th wheel, and Breschel got the perfect leadout. It looked like Mcewen would take him, but MCewen could have dies and Breschel might have held on and had the strength.
Breschel took the line to the barriers at the start. Mcewen got in on his shoulder but side by side so the marginal slipstream benefit would be his. 'dats racin, both taking the line to the barriers where the win is calm.
Breschel appeared to get antsy, nervous as Mcewen had his shoulder and was rding him on that line. He corrected, but OVER-corrected and really took Mcewen by surprise as Mcewen is the most talented handler in the peloton. It looked like Breschel did a mini hook, NOT intentionally, just in the act of over correcting as he was throwing his bars to and fro. *Note this correction could have come after they locked bars, so not 100% on it.
Mcewen's bars or brake caught on Breschel's bars and he went down, and then made Breschel go into the barrier.
My take, if Breschel was an experienced sprinter it would not have happened. I don't see how MCewen can be dq'ed *except in expediency* when Breschel took the line to the barriers first. It also looked as if it sloped down that way too. If one takes the view that a racing line can be taken to the barriers, when the sprint begins, and then obviously corect the line along the barriers, versus a tangent from the sprint start to the end line on whatever angle as long as it is at the finish line, and not to the barrier, Mcewen should be clean. The overcorrection by Breschel was just as much to blame than Mcewn getting in close to Breschel. Besides, worse is seen every day.