You say these things like they're not completely insane even by my standards.

[And his standards are high, Davesprite. Let him tell you. It's just that as soon as you involve time travel, his eyes cross. About which he is frankly a little relieved.]

So time was - supposed to allow you to save John's life. At the price of your own - future? Clearly you were not erased. Which feels a little like cheating, really. Either you're doomed or you aren't.