In canton mass last year a runaway freight car cut threw a "derail" and smashed into a commmuter train. Over the years i've heard of other runaway trains/cars cutting thu derails. I guess you never here about when a derail works because it does its job and sends the car off the track. My question is what percentage of derails fail? If there not working with loaded freight cars whats the point of having it? Should they throw these derails away for a split switch or some other better design?