User blog comment:ImperiexSeed/Sam's NOT the hero of the show!/@comment-95.112.146.189-20150710105114/@comment-93.132.35.22-20150713181518

Well, i am quite sure they would the spell let the spell happen even if they had enough time to prevent it. The Sam and Dean of Season < 6 would never let this happen, not with this tremendous consequences. Seems for them everything is fine as long as they both live, if the universe crushes - just let it happen.

The last time one of them made a true sacrifice was when Sam did not try to free Dean from Purgatory.

It like them anyway, it's quite entertaining  to have anti-heros/ villains as main characters.