the john carter series long swords were described by ERB more like longish side swords. in spite of the gravity being less, the length is still governed by how long your arm is, and whether you can sheath/unsheath it. a human could carry & use a longer tharkish sword, but much like a two handed earth sword, would have to carry it over his shoulder w/o a scabbard. or on his animal mount or air car. for an earth human the extra weight would not matter much.
JC's leaps were a bit exaggerated tho in the film. liked his doggie tho (actually a martian lion)
the film ones look distinctly filipino influenced with a few extra claws and hooks to add alien-ness. the double ended ones are just silly. (as is the starwars/star trek versions) no one in their right mind would use one, even with four arms. they are a solution looking for a non-existent problem. i see a katar in there too, somebody in the props dept. must have an indian connection
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