With that sort of injury caution has to play a part, he's been out a long time now, so much so it's as if articles read that he is being 'rushed back for the WC' rather than the timing being perfect. Any element of doubt from the medical staff then he shouldn't be risked, life goes on after the WC and that is the big key point. Any wrong decision can end his career in seconds, and that goes for anyone. Look no further than Essien in how a career can just nose-dive after a big injury.