Froome did not look invincible this year. In previous years, he rode away from his competition on the mountains. This year, he couldn't do that. Aru apparently became ill the last few days and dropped off the pace. I have to question the organizers for having so few mountaintop finishes and a time trial on the penultimate stage. All Froome had to do was mark his competition on the hills because none of the mountain guys could time trial like Froome.
It looked like the three strongest riders this year were Froome, Kwiatkowski, and Landa. These lieutenants of Froome were amazing to watch.