I guess i fit comes off the hitch, but stays tied on with chains, when you brake, there's no braking on the now uncontrolled trailer - and now theres a tow car and a trailer on an unguided course to the nearest accident . . .Out of interest why aren't chains used instead of breakaway cables? Seems to me the safest situation is to keep it attached to the towing vehicle should the main coupling become detached. On a motorway a trailer becoming detached and slamming it's brakes on in front of you and then usually crossing the carriageway as seems to be it's favoured route can't be a good situation, surely it being dragged by the original vehicle via chains is a better solution or is it guaranteed to flip the trailer/towing vehicle?
American trailers, and there super duper dangling wiring connections may well stay electrically connected to get the trailer brakes working will still hanging on the chaines?