Recently Róisín Stapleton went in search of a one-way train ticket to take her back to Dublin after spending a weekend with her family in Mayo. When she asked about the price at the Irish Rail office in Castlebar she was told that a one-way fare was €30 while a return cost €42. As her “more impoverished younger brother” had plans to visit her for a weekend soon afterwards, she decided to buy the return ticket and allow him to use it on the return leg of his journey, saving himself €12.

This makes economic sense everywhere but trainland. When Stapleton’s brother went looking for his one-way ticket from Castlebar to Dublin last Friday he was told that “there was no such thing on a Friday” and that passengers were obliged to pay €42 regardless of whether they intended to use the return leg or not.

Stapleton points out that for road safety and environmental reasons “one would expect to be offered an incentive to use public transport for longer journeys and at weekends, but it would seem that, using a very particular form of Irish logic, one is in fact penalised. Any insight that could throw some light on whatever form of logic informed this policy would be greatly appreciated.”

So we contacted the train people to find out what was going on. A spokeswoman said that Irish Rail offered a €30 “discount day-saver fare” from Monday to Thursday and on Saturdays. On Fridays and Sundays, which are obviously the busiest days, the discount is withdrawn and only two fares are available - the €42 single fare and the €45 monthly return. So, while our reader’s brother was wrong when he said that Irish Rail don’t sell one-way tickets on Fridays, they do seem to price them in such a way as to render them very poor value indeed.