If you have an example of a hitch pulling out of a pickup, and the trailer remaining on it's wheel carriage, I would like to see that.
Trucks/trailers that have rolled don't count. The break-away cable isn't going to be an issue in that scenario.
The only scenario where this is going to matter is when the hitch pulls out of the pickup and remains connected to the trailer king pin. If the hitch and the pin separated, the weight of the falling hitch head would still pull the break-away pin.
Anything can happen of course, but a scenario where this would matter is so against all odds as to not be of any legitimate concern. The odds are better that a pin box would separate from the trailer, in which case the switch also would not activate. From that standpoint one could argue that putting the switch on the pin box, instead of the frame of the trailer, is poor design. Somehow we live with those odds, because we are realistic beings with common sense. Most of us anyway.
