A friend of mines dad is a fuel man & he mentioned that the interlock is capable of being over ridden in case of an emergency such as a fire & the rig needs to be removed from the scene connected or not. Faults he said are sometimes found in the system & then over ridden by the user. He mentioned that the same thing happened at Tulla in the mid 80's when a truck drove off with the hoses still connected to the wings under surface, lots of dollars latter the plane was fixed.
FG