frfly
Perhaps Aer Lingus attract more business passengers and EDI because;
a) Business passengers are not (generally) as price sensitive, and
b) when things go badly wrong, FR cancel the flight, while Aer Lingus will
rebook you, including your onward connection if relevant - even if it means putting you up in a hotel.
Must add, that in my experiance so far, I have never had a significant problem with FR.