Well, in the 50+ years driving my Augusta, I've had a few incidents of rear doors coming open, all without damage except one way back in 1962.
Four up in the Augusta, we were driving home at a good clip on a lone country road in the middle of the night as the left rear door opened and disappeared in the night. Althought I stopped immediatly it was difficult to find the location of the incident and as the road was elevated in relation to the country left and right it was difficult to put the light from the headlamps in good use. Anyway, it took close to a half hour to find the door in the darkness. Both the brass hinge pins and the cable were broken and the window frame distorted. Lesson learned!
Regards Karl