I may need to skip the last leg of a multi-segment return flight. I would get off in DFW and miss the final segment. Can I purchase a one-way flight on AA from DFW to a different destination city without causing any complications? I assume it is no problem if I do it on another carrier, but would like to support AA and get miles.

Sorry if this has been covered already. My search did not reveal a thread directly on-topic.