OK, let's dream a little
No harm, who know, it could work.
Let's suppose for a moment that EI could do a really good deal with Airbus on some 380's, and that Dublin could get it's act together to be able to handle them ( Fat chance, but this is a dream remember).
Given the flight time to the East coast of the US, there would be the potential for a 380 to do 1.5 rotations a day, so 2 of them could provide 3 flights a day each way to the East coast, a flight every 8 hours. Given appropriate feeder flights from the right places, and appropriate pricing, and the advantage of pre clearance at DUB, properly marketed, that should in theory be quite a nice little earner, as anywhere further east will make the flight times just a little too long for that schedule to be comfortable.
OK, it's going to put the airframes under a bit of pressure, and the infrastructure at DUB has no hope at the moment, but it could be made to work. If freight could also be interlined, I would suspect that the load factor could be very good, as that length of route should allow a good load of pax and freight to be carried.
Only a dream, but it has to be worth a little bit of thought.