There really should be a more descriptive term for back to back ticketing. I don't know what that would be, but the term "back to back" invites people to think that they're doing something illegal when they're not.

For example, I have to go to ATL late this week. I booked one 1-way flight from MEM-ATL on Thursday and one 1-way flight from ATL-MEM on Friday. Until a few days ago I had never heard the term "back to back ticket" and, after reading this thread, got curious if I had done something illegal.

(For those that are curious, I booked one trip through DL.com and the other trip through Travelocity.com. I'm a Travelocity.com credit card holder, so I'm motivated to buy through them. I also had an eCert I wanted to use. So that's how this screw-brained itinerary came about...)