So, the lesson here, as they should have known, is never to let the director do the marketing. No, people in 2012 don't instinctively know who John Carter is, and they've seen special effects before.
Here, then, is one example of an ad that would have doubled attendance and made it successful:
SNAPSHOT OF HELIUM PALACE WITH BABES IN ARMOR
"Before Star Wars"
BIG, LUSH PANORAMA OF HELIUM
"There was John Carter"
CARTER LEAPS INTO MELEE AND STARTS SLAYING GREEN MARTIANS
"From the creator of Tarzan"
SHOT OF AIRBORNE GUNSHIPS RAKING EACH OTHER WITH FIRE
"And the director of Wall-E"
CARTER SHOUTS, "STAY BEHING ME, THIS COULD BE DANGEROUS" AND WADES IN TO KICK ASS.
DEJAH THORIS CATCHES SWORD, CHARGES IN FRONT OF HIM AND STARTS GUTTING BAD GUYS. "LET ME KNOW WHEN IT GETS DANGEROUS."
"A century old epic, in a universe not quite our own."
MORE LIGHTSHIPS SHOOTING, ARENA SCENE, CLOSEUP OF SEVERAL HELIUM CHICKS IN ARMOR SLAYING ENEMY, AND SEVERAL BUFF, HELIUM MEN IN ARMOR DOING SAME.
"John Carter of Mars."
There y'go, Andrew Stanton. I polluted your pure vision of JC, but sold the fucking movie. You're welcome.