I didn't know this was a new thing...I used to take the Delta NRT-LAX connecting flight years ago. Are they reinstating the route?
One time I used this flight was on connection from JFK. The flight from New York arrived late and I was sure they would rebook us in some way, but they held the KIX connecting flight for us. After getting off the first flight we were rushed to the KIX connection and getting on it could see it almost already full...with passengers who came on other Delta flights, and were sitting on the plane for god knows how long just waiting for us! I guess Delta doesn't have much flexibility for passengers who get stranded between Tokyo and Osaka.