One driver in this video smartly spots one indicator that there will be a crash ahead on the highway. Two drivers don't.
Here's how the uploader described this dashcam video.
So I'm coming home from work in Houston and traffic is heavier than usual. I see the helicopter early in the clip and know that there must be some kind of wreck up ahead and I slow down to allow myself some stopping distance. You can see the Toyota Prius speed up to my right and behind the Prius is the two trucks barreling ahead like crazies. Well, I guess a crash was inevitable. The truck driver had the stupidest look on his face as I passed him.
This is a lesson that there are 'signs' that you can read in traffic, watch for indicators and predict what's about to happen ahead of you.