How do you figure they are back to back. On my first ticket I am flying to LAX and staying there a week. Then I fly back to SFO.

With my second ticket new ticket I fly to LAX and stay there for a week. Then I fly back to SFO.

With a third brand new ticket I fly to LAX again and stay there for a week.

And so on and so on. In each instance I use the whole round-trip ticket exactly as booked and comply precisely with the airlines rules. Unless the airline can come up with a way to limit the time between separate roundtrips, which of course is ridiculous and counterproductive and impossible, I believe this is perfectly "legal" whatever that means.

If you don't think so, please state clearly and precisely why not. (In your own words please, and prefereably not too many of them.) I was a blonde for a long time and developed difficulties comprehending long technical explanations.