I think you need to look at this statement in the context of the EI privatisation; every analyst, their granny and the dog and their granny's analyst is saying that EI needs to develop long haul; what better way to undermine EI than to threaten this. All he needs to do is to make it plausible in some way. The reference to the SNN stopover suggests a focus on the Irish market (whereas the overall Open Skies would allow him to do this from all across Europe), so that kind of suggests to me that they're looking at spiking EI and if they can undermine EI on long haul, they can really put the squeeze on them on short haul ...
That said, I don't think it can be ruled out. If this website were around 15 years ago and someone had said that there'd be an Irish airline which would be one of the biggest and fastest growing in Europe, using only 737s, you'd probably have doubted it; I think there are fundamental differences in long haul, not least because people want their creature comforts, BUT we will get to a stage of having Open Skies and indeed, the Shannon stopover could be lifted (or at least greatly alleviated) by next month, so he could well try and dip his toe in the water.
If I had to take a guess, however, I think it's something he will look at, but right now, he's just saying it to undermine EI.