I agree. He could have gone with Sastre and Menchov, but then he waited for Vino because Astana told him to. The reason for it I think is because the team is Kazakh. Vino is very far behind all the the contenders though, and it will be tough even for them to catch Rasmussen if he didn't use up too much in the stage. However, I think that Astana will soon either push Kloden forward as their contender, or launch an attack with Kloden and Vino in the Pyrennes (provided Vino gets better in time). If Astana doesn't, they might as well run around like a naked Borat (did you see him in the stage? lol).They'd better push him forward whatever happens or I will be very dissapointed.
It was a gamble, but they may be feeling that there is enough time for Vino to continue to improve. It was also unclear how much time Kloden would have gained had he headed off. I think they are or were betting on Vino to ultimately be the strongest of their riders.