Burning your bridges?

What I want to know is why did they leave them on the bridge instead of pulling them off:confused: :confused: :confused:
 
Common sense

Well common sense would be to pull the cars off the bridge, but as the original post started, they were following regulations stopping the train in the first place. I guess pulling train cars off of a burning bridge isn't covered in the regulation manual.
 
I think they mentioned something about molten metal from one of the railcar trucks. When they stopped, could the molten truck have fused/welded itself to the rail, making it impossible to pull the cars off....

Just a thought...does that idea make any sense...