I believe the tunnel at Newport is not part of it due to landowner issues.
I don't doubt the success of the above but let's not forget that region was already on the tourist map for many many decades, probably kick started by the MGWR, and the results may not be identical in less traditionally touristed areas. Dungarvan was an up and coming town in it's own right before the greenway appeared.
There's current debate over a portion of WRC to become greenway, the scenery and towns there are, let's be honest, quite pedestrian at best, unattractive to tourists at worst.