I wouldn't say that. He's #21, Astana wants yellow, this was his terrain, and everyone in Astana was playing it hard but conservative, content to choo-choo the peloton apart and manage the attacks from other GC's.

AC saw the attacks going no where, felt fresh & good, probably thought that if this is what Evans, et al, had, then he could overtake them and, BLAMO, went for yellow. It's his job, regardless of the plan.