Where will the growth come from? Will people from Dublin/Limerick/Galway suddenly decide to fly ORK-LON? No, very few will. Will 100,000 extra Londoners suddenly decided to visit Cork? No they won't.
Ryanair will still be alot cheaper, Cityjet realistically will only be Competing with EI, which they will steal passengers from.
I can't see growth coming from anywhere?