I actually thought about that possibility about 20 meters before the finish line (funny how much can go through your mind in so short a span of time).
But the possibility flashed through my head, "What if Scott's timing chip is on his lead foot and mine is on my trailing foot when we hit the line?"
I determined that I would run hard all the way through the finish (you'll see in photos that I have a good stride on him only five yards past the finish) - so that if the finish camera failed for any reason, the visual memory of me getting to the tape first would be strong in the finish line officials' minds (in case the chip scenario came true ... which it did).
While it was easy to determine finish place in my case, I wonder if athletes who finished in bunches further back in the pack were separated with as much diligence. Since it's torso and not foot-with-timing-chip that determines place, were all close finish places evaluated by photo finish? ... Harrier?