Some cities are cheaper to fly to/through than others. I am going Boston to London in business in a month and a half on this routing on OneWorld: BOS->JFK->DUB->LHR. The total price (in business) is cheaper than the RT from Boston on AA in Economy Plus for the dates I'm traveling. From my research so far (using Google Flights to find the fares), Dublin and Madrid are by far the best business class trans-Atlantic fares I can find on AA. I'm flying coach from DUB to LHR, but it's about a 30 minute flight (from wheels up to wheels down) so no point in paying the extra price. I don't mind the layovers as I can use the lounges and it's been too long since I've last been to Dublin (since they eliminated smoking in pubs for anyone that can remember that far back - I'll be able to see all the way across Temple Bar).