I think cost-benefit analyses are often worthless because they are nearly always wrong. Laughably so in the case of Metrolink. The benefit will be orders of magnitude greater than what the bean counters have said.You missed my point which is that parochialism is not confined to rural areas. Metro will be a hugely expensive project, many multiples of the cost of rural broadband and will take years to complete and will benefit only a portion of the population. Its a good example of how worthless a cost benefit analysis is when deciding on big infrastructure projects - Ardnacrusha made no financial sense when it was built.
It will be considerably less for the broadband plan, but I still think it's worth doing. Investment in infrastructure is more often than not beneficial overall (notable exceptions like the Western rail corridor aside).
The parochialism thing is a different issue. I despair sometimes that the worst objectors to infrastructure in Dublin are from other people in Dublin eg the likes of the comfortable well-off types in Ranelagh led by Michael McDowell. So, if your point is that Dublin people are just as parochial as the rest of the country, then I agree with it.