Yea, if you read the hundreds of posts, you will find some 3:21 guys who brag they get better milage than a Tesla or at least a Prius. Many think milage has only to do with mathematic equations depicting rpm with no reguard given to how hard the motor works to maintain those rpms.
Drive a smaller motor and this becomes even more apparent. Go on the jeep forums a bit and you will see guys going up to crazy 4.56 and up seeing milage improve because the motor is not lugging along to try and keep up when they put real tires on.
But you know, some just have to justify their decisions, even when wrong.