Frank wrote:Trams are usually pretty slow. How fast are these likely to go? Will there be any saving on journey time?
For safety reasons trams are pretty slow when they are running on the street with mixed traffic. When they're on dedicated lines they can easily run as fast as ATW's Pacers. They also have much shorter stopping distances meaning a service like Merthyr > Cardiff could include additional stops without adding to the total journey time.
Having said that, the differentiation between train and trams and light and heavy rail is rapidly disappearing. If freight traffic is excluded from the core valleys network there's absoultely no reason to stick to heavy rail.