With EK's reputation, they should be operating with good load factors out of DXB for NYC. Therefore the only thing that a stopover in Ireland would do is increase the operating costs of the flight and totally inconvenience the passengers.
There is nothing worse than getting woken up after seven hours to sit in an airport for one hour and then fly for another 7 hours.....
The A340-500 will make the trip non-stop.
Mutt