He said before the start that he had trained less on punch/short efforts in order to be better at the long ones. I suggest we wait and see before jumping to conclusions. Surely he wouldn't have even tried to attack if he felt like he was cooked right there. And when you tow a group to the line, getting outsprinted by most of the guys that were in your wheel, is like the most obvious thing to happen.
What is clear, is that his acceleration is MIA. Whether that is a result of his training schedule as he somewhat predicted, or because he's simply not got the legs, i would wait a few days and see how he fares in the actual mountains. He lost 5 seconds, not 5 minutes.