Yeah, it's not the most brililantly written piece. A bit rushed, perhaps. But I agree with the point it's making in that it's far too inconclusive to throw the book at Sagan.
I still reckon the full DQ is harsh, especially as a speical case upgrade on the original sanction. Looking at the gif on that page, Cav was gone before the elbow came out and to me it looks like Sagan is using it to balance after Cav leans into him in a last gasp attemt to stay on two wheels. As Sagan's elbow comes out so does his left knee, again to provide a stabilising, balancing effect.