Dear Viking,
Germany adopted the RZ-1 parachute harness because it was developed from those worn by World War 1 observation balloon crews. Herman Goring wore a similar harness during 1918. Italian paratroopers used that wide belt as the basis of their Salvatore harness. The Salvatore/RZ harness solved the nuisance of line-twists by adding a metal swivel where all the suspension lines and risers converge, above the jumper’s shoulder blades.
These days, skydiving students are taught that line-twists are a “nuisance.”
On a personal note: I have suffered line-twists during hundreds of skydives, but twists were only bad enough to need a reserve parachute twice! Both those line-twists to reserve malfunctions were on tiny sport parachutes invented after 2000.
The primary disadvantage - of the Salvatore harness - is the awkward landing that ideally includes a forward roll .... requiring extra time to teach.
Despite extra training, Salvatore landings still increased the incidence of foot, knee, elbow and hand injuries, the extra padding on feet, knees, elbows and hands worn by WW2 Italian and German paratroopers.
The other disadvantage of the awkward landing angle was that it limited personal weapons to pistols, knives, grenades and maybe submachine guns .... not a major deficit during clandestine raids, but as soon as you lose the element of surprise, long guns are desperately needed.
A second disadvantage of the Salvatore/RZ harness was the lack of quick-releases. QR can save lives during water landings or when being dragged by high winds. RZ 20 harness introduced 4 quick-release buckles, a quick-release box was not introduced until RZ 36. QRB have all major straps routed to a metal box in the middle of the chest. A simple turn-and-punch releases all important straps from the QRB .... mighty quick when you land face-down in water!
Master Corporal (retired) Rob Warner CD
Canadian and West German Army (static line) jump wings
FAA Master Parachute Rigger: back, seat, chest and have sewn a few lap packs
More than 6,600 total parachute jumps including more than 4,000 tandem jumps
Civilian skydiving instructor: static-line, IAD and Progressive Freefall