Maybe it has ? The Tories were so dire in the election campaign that if Labour had been able to find someone with sufficient credibility that their own MPs would support them then perhaps they might have won.
As for Corbyn winning at a second try, that might well depend on how far up the learning curve the much-touted youth vote has managed to get. As noobs on the political scene they might be forgiven for having been confused by Corbyn’s position on tuition fees. But when he came out and clarified it (after the vote, of course) they might just have felt they’d been misled.