As you know, when there is a delay, one would not know when the delay would be resolved. She knew as early as 6:30 or even earlier that there was a delay. She would not know when they were flying because there are a lot of complications with flight crews, weather, the domino effect of delays on other planes.
With him knowing of an issue, I doubt if he raced off to kill the kids . There would now be too many variables. She may not arrive until the next afternoon.[/QUOTE.
The what if’s about the flight delay do not apply here because they both knew how long the delay was going to be, a time was given, there was not any unknowns. I think the only variable is her delayed flight quite possibly did not leave him enough time to follow thru with staging the scene as if they had left.