Welcome to Flyertalk, checkers.

Back to back ticketing is when you return to your origin on a second ticket before you complete the minimum stay of your first ticket.

For example, you live in AUS and need to be in LA from Tuesday til Thursday. You find that tix without a Sat night stay are $1,500 return. But if you book your ticket Tuesday to Sunday, the price drops to $300 (because of the Sat night stay).

So you book that ticket and another ticket LAX-AUS Thursday-Monday, also $300 because of the Sat night stay. You fly AUS-LAX on Tueday on ticket #1 and on Thursday, fly home on the second ticket LAX-AUS. You just saved $600. If you planned the second segments well enough, you might have coupons for a second round trip. And if not, who cares? You cut your airfare in half.

And the airlines didn't like it. Not one little bit. THAT's back to back ticketing, and it violates AA's rules. Do it enough and AA will do bad things.

That said, what you're talking about is end on end ticketing, and it's almost always OK with AA.