The 2010 Dublin-Limerick timetable introduces an 0730 ex Thurles which departs LJ for Limerick 0800 arriving 0829. Due to the lack of a straight line connection ex Thurles it is actually not the worst idea for a commuter service as it's tough for the car to compete (except for UL/Plassey Tech Park).
At present the incoming Waterford/Clonmel/Cahir arrives at 0812 and due to a wait for connections doesn't make Limerick until 0915.
What time would the Waterford service have to arrive at LJ to get there first and to not impede the incoming Thurles, and how much would have to be done to the route to increase trip speed sufficient to get there (reliably) by that time without advancing the departure time ex Waterford significantly (having been already advanced for 2010 from 0635 to 0630)? My understanding from
a post by KC61 on boards.ie is that the timetable is for 40mph but the route should be capable of 50mph.
The reverse trip (dep Lmk 1800 arr LJ 1831 dep LJ 1845) is not great but it's at least doable for 9-5ers.