"My condition's been very good, but I've never looked to push right to the end, I think that you can see this from my face," Nibali said. "When I get to the finish, I've never given everything because there hasn't been the need. You need to think of the following day's stage, where you never know when you could have a crisis or something. So I've never had to push too much."
So, from the man himself. Obviously he could be lying, and I'm sure many a AC and Froome fan will say that he is, but if true it's a little sad. The leader of the TdF should be pushed to the limit at least once.