flarepilot
You may not be far off with the tunnel vision idea.
The captain may have been focusing on their approach speeds and considering a floating possibility on a reasonably short runway.
But, from what I remember on this thread, the approach speeds did not seem overly high, especially for WN.
However, booth pilots had a lot of time in the 737, and would know the stopping capabilities of the plane.
The NTSB should have some really good data on this one.
Regards.