I find Mr. Walsh's remarks quite interesting. EI at the moment codeshares with UA but also KLM. I have flown plenty of EI-DL itineraries as a result as well as EI-UA a few times. These are easily bookable and very competitive in terms of fares. But EI-AA still to me often shows bad fares, bad connections. In fact, if you wish to book ORK-anywhere in the U.S., you will be able to do that online via KLM, UA as well as BA but not EI or AA.
All of this is pretty much where it was a year or two ago and essentially is indicative of an Aer Lingus that's primarily an intra-European carrier, which is happy to leave good chunks of the ex-Ireland transatlantic traffic to larger airlines. And with no preference shown to OneWorld at all. Given their relative fiscal success recently this seems to have worked out for Aer Lingus but surely even Mr. Walsh won't be able to sell that to AA as a sustainable state of affairs. AA surely must push EI eventually to take its place as a feeder for their network.