I'm with postman plod on this one. Comparison of fares is never easy and there will always be the extremes like the one Flip Flop flyer identified. A different example:
LGW-DUB
Outbound 16th July
Return 23rd July
Ryanair: £98.52
BA: £83.30
Same airport, same route, same aircraft type even. Only you get to fly with a reliable company who you know will get you to your destination, regardless of aircraft going tech, adverse WX, delays, or any other excuse O'Leary uses to strand his customers once he has fleeced them of their cash.
Sure, somebody will probably quote a route where BA is more expensive. But my point is, BA are competing with the no-frills boys. Ask any passenger, particularly business passengers, which company they would choose if both were quoting a similar fare, and I guarantee 9 out of 10 would choose BA.
Watch your back O'Leary, your time's up.