They've been planning to take Froome all along, he is a rider they are really trying to develop into a threat in the mountains. I agree that his form has been patchy at best this year, but the DS obviously has faith in him.
Kurt's been taking the entire season pretty easy really. Remember his season didnt start till Tirreno because of his collarbone (where he finished in the hundreds every day bar the last), didnt finish 3 of his next 6 races, and has only raced Bayern Rhundfart, and the Tour of Luxembourg since. Hes been taking it very easy and concentrating on training. He will be ok, and his role will be road captain rather than hunting down wins or anything.