The idea that journey times between Dublin and Wexford could be "reduced by about an hour" seems rather optimistic to me. Current journey time via Wicklow is about 2:40. Current journey time to Waterford is about 2:15, though that does involve a reversal at Kilkenny.
I can see there being a Waterford - Wexford - Europort - Waterford triangular routing if the via-Waterford scheme came to pass.
2 hours exactly on the 16:15 Fridays from Dublin, calling at Athy and Carlow only and without the reversal, and 2 hours 1 minute on the 16:05 on Friday and Saturday from Waterford with a stop at Kildare too.