of course there is the theory of compatability, that only a sperm with a specific set of chromosomes will ever succeed in fertilization, as the conditions of the womans body at the time would only allow THAT particular sperm to "win". Of course this doesn't matter since a womans chemical makeup as well as other things in the "nether-region" never stay constant, and so even 5 seconds COULD (theoretically) change who wins.
in the state of the debate, no difference in time of intercourse would even be needed since you were actually ADOPTED! Sorry to tell you that.
But since I don't believe in time, and therefore that anything COULD have been different (notice, though, I am not a determinist), it doesn't really matter cause you COULDN"T have been different.
Before I'm nailed on the "i don't believe in time" thing- let me explain. I believe time is simply the minds way of spacing out memories, just like space is the minds way of spacing out objects.
but that is all. SO time travel would be impossible.