Gravity doesn't work even remotely like it does in the Barsoom stories. Carter's jumps should be more like those of Neil Armstrong on the moon that the Hulk like bounds we saw. Burroughs had a very weak grasp of science and was writing at the beginning of the 20th century when a lot less was known.
Which was what I said in a previous post. Which also brings us to the fact that now we do have an extensive amount of knowledge on Mars, and that this is the movie version which we are working with and that particular version is different from the Book.
I can see how you'd make this assumption from the movie, but the books depict Carter as superbly conditioned, and amazingly skilled. It's his swordsmanship, not his Martian strength Scar has to worry about.
Again... Not the books. This is the movie version which we are talking about... And speaking of the movie version, I just remembered that there are TWO movies of John Carter. Disney's version, and of course the Asylum's version.
Also, regarding his Swordsman ship... Scar is actually quite talented with a combi-staff. He's shown to have pretty impeccable technique with it.
For realistic math: the gravity of Mars is 37.9% that of earth, so a human on Mars would theoretically be capable of lifting 2.64 times as much weight. He could leap higher as well, though no more than 2.64 times what he could on earth and probably not that much.
So what you're saying is that despite Carter's strength on Barsoom, realistically speaking he would barely be Above Peak Human Strength. Now I can't tell you what the gravitational pull on the Yautja homeworld is like as far as definitive numbers are concerned, what I can tell you is that the planet has an asteroid belt around it similarly to how Saturn and Jupiter does as well, implying a very strong gravitational pull. More than likely, this is a factor in the strength of the Yautja as well as their anatomical differences and musculature, as well as bone density from human beings. On Earth, we know that they are superhumanly strong and the average Yautja-- and I mean your run of the mill Predator from Unblooded to Blooded in rank are somewhere in the 2 - 5 ton in strength range. And this is taking in the Expanded Universe, crossovers not counting. But there are Yautja who are stronger than the one's we commonly see... Some being crazy strong.
So really... It wouldn't matter if Carter had the buffs as far as Barsoom's gravity is speaking because Scar would still vastly outclass him.
For ERB math... it can't be done. In the early stories Carter's strength is wildly inconsistent. Sometimes he's leaping dozens of yards and beating down Tharks and white apes, other times he's a little stronger than an athletic Martian man. In the later stories he pretty much drops the strength gimmick.
Because you said it yourself... ERB had a weak grasp of what Mars was really like. Also, there were different writers for the books as well.
For the film version, it's easier to work with because modern interpretations of science fiction do use real science to make such works more believable.