I believe it was down to how a German parachute RZ rig (
Rückfallschirm, Zwangablösung or “Backpack Parachute, Static Line Deployment”) was attached - one point mid back. The advantage was it could be used from a VERY low altitude the disadvantages were many (no steering, low weight, forced posture, etc). I never understood why the Germans, masters of efficiency, didnt develop / copy a better design...
