I never heard of
www.dart.ie before i read this thread but the reasons for it, as said abovce, are a micocosim of all that is wrong in IE's managment.
As for "exact fare" the gist i got from the original thread on boards was that the person atthe ticket office simply had a note that the ticket office didnt have enough change for. That's fair enough.
There's exact change only on DB, has been for years and years. In relation to Chip and pin, it can hold things up a lot. I use it all the time and sometimes it flies sometimes you can be waiting a couple of minuites for the dammed thing to work. I dont think its the solution to a busy surburban station during rush hours.