Ah, yes but if you really want to cry, have a look at the
BVG (pronounced Beh Feh Gay) in Berlin. In particular the section on tickets and fares. I was in Berlin for a holiday a couple of years ago, and the ticketing system was a joy to use.
Seeing the gulf in best practice between the integrated system in Berlin and indeed other German cities, and the confused excuse for integration in Dublin would make you want to give up completely.