I really think that was all Webber's fault. Vettel had a huge run on him down the straightaway, and Webber made 2 moves to block Vettel, which just cost Webber more speed. So Vettel took the inside. If Webber was smart (not just b/c they're teammates, but for a racing tactic) he would've moved over to the middle of the track, or wider, gave Vettel the inside, and then try to pull an Over-Under on him after Vettel went too deep into the corner. Being that they're teammates, Webber should've stopped blocking after his first move, and give Vettel the inside. I would've done the same thing if I was Vettel, even the "Webber's crazy" hand motion.
Steven

