This would have made much more sense that the route the DoT in its widom DID choose for a tram-train trial i.e. Huddersfield - Penistone - Barnsley - Sheffield where the tram bit is only a very small part at the Sheffield end.

It doesn't really matter which route the DoT choose as I don't think they have any intention of developing the Tram-Train concept as such. I get the feeling that they are after a replacement for the 14x series trains that is cheaper than a conventional DMU.
Tram-Trains built in mainland Europe would probably meet our heavy rail safety requirements and still fit our restricted loading gauge without too many mods being needed.

Adelaide Metro, or Trans Adelaide in South Australia are in the process of developing tram-trains.

They are purchasing 15 new dual voltage trams as well as 4 additional Flexity Classic trams which they currently use.

The new dual voltage trams will operate alongside electric trains and use the existing Outer Harbor line and then travel to AAMI Stadium and West Lakes on a new track built from the Grange line.

Another extension will be built from Semaphore, linking back through the heart of Port Adelaide from Rosewater. The 4 additional Flexity Classic trams will be added for the initial Entertainment Centre service.

This will be the first 'tram-train' system in Australia.


NL.

The tram-trains for Huddersfield-Sheffield are going to be diesel operation only. If they want to try dual powered vehicles then joining the Manchester Metrolink line at Altrincham is probably the best route and then if the East Lancs to Bury needs a regular passenger service that would be another possibility.

Sorry, but the manchester metrolink is really a tram-train with a max speed of 50mph and it runs at this speed in the counry sections of old railways.
The trams have to switch modes at the city/railway sections.

Although the Manchester-Bury and Manchester-Altrincham sections were originally heavy rail lines the Manchester Metrolink vehicles are NOT "tram-trains" because they cannot share their tracks with "real" trains. As they are only expected to come into contact with road vehicles and other trams they have not been built to the same standards as heavy rail vehicles.

Oh right I get it now.
Could they not be towed on normal lines as they are standard gauge?

Good question.
The Metrolink vehicles are standard track gauge but are they wider than a normal train? If they are normal width then I can't see any reason why a Dellner coupler fitted loco couldn't tow them although obviously they wouldn't be allowed to carry passengers.

At altrincham and various other smaller stations, the original Manchester, south junction and altrincham railway's platforms are still used and at navigation road, the station is shared with northern rail trains.

I have a copy of the Metrolink handbook and a Metrolink tram is 2650mm at its widest point (doors) They should, in theory, be able to go anywhere on the rail network that has the most common loading gauge of W6a (2820mm above platform height and 2700mm below)