I was on the bus today again and on the way home the journey wasn't too bad. It took 40 minutes from town to my part of Lucan and with a few tweaks it could be nearer 30 maybe even under.
Why doesn't Chapelizod have it's own bus route so the 25A can go down the N4 bypassing Chapelizod. That would save nearly 10 minutes right there. And if the bus driver didn't have to take fares and the ticket machines didn't take in your card, rather you tag on and off like an Oyster card in London.
That would get the journey time around 30 minutes and that is not even considering traffic light sequences or the routes once the bus gets to Lucan.
It can be done with a bit of effort.