i dont think anyone is actually ''ROOTING'' for Henne to fail. i think its more that some people feel he is not the answer at qb and dont think hes to good of a qb.
personally, after his 09 season, i was in love with henne despite how he still had more ints than tds that year. i was so excited to see what he would be able to do with marshall in 2010, and the offense as a whole.
unfortunately, after last season, my confidence dropped in Henne, as many others did to. It wasnt just the fact that his stats were bad, it was just watching him play. He stared down his receivers to much making it obvious who he was going to throw to, didnt seem like a leader like most qbs are, he had no pocket awareness, and it was just a very ugly scene in general. We can all sit here and say how henning was a reason, and i hated dan henning and thought he was terrible last season and am as happy as anyone that he is gone, but that does not hide the fact that henne was god awful last year, not just stat wise, but just in everything he did/ didnt do.
In the end, all the people who have lost a little confidence in Henne, including myself, would like nothing more than to see him lead us to great things, and the ultimate thing, the superbowl. we would all be happy and their is not one person here who actually would be pissed, despite what some people may think, if henne led us to great things. In the end we just want to win, and if henne can do that and rebound we will all be happy. No one is actually rooting for him to fail.