American Airlines recently announced a new partnership with Cathay Dragon to codeshare some routes in Southeast Asia. While new partnerships are nice to see, what will really change? Both are already oneworld members, and as such I can already easily book a single travel itinerary with both airlines. Moreover, if I have two itineraries booked that connect, I can check my bags through to the final destination from the other airline and receive my boarding passes for the second itinerary when I check in to the first.

So then, what benefit does such a codeshare actually bring?