In message , at 11:13:05 on Tue, 22 Oct
2019, Recliner remarked:

Economics is a very big component of "workable".

Not in most dictionaries.

You can make almost anything "work" if you throw enough money at it.

Now you're just arguing for argument's sake.

Pointing out basic economics doesn't meet that definition.

Things have obviously changed six years later.

Not necessarily. This could be just another concept demonstration.

No it's not. The trains were ordered in January, and the service starts
next May.

Too far in the future to predict it won't get quietly dropped.

Hardly. The train order was placed ten months ago, not 'far in the future'.

Next May is too far in the future for us to predict today that it will
actually happen.

My main reservation is that the work is being done by Wabtec (Brush)
Loughborough, which seems to be late with everything.

I've recently been reading about 2014 ambitions for East-West rail (for
a discussion in another place). The one consistency is that pretty much
all the prerequisites upon which that plan was based have failed to
materialise either on time (eg Ely North junction by 2016, or other much
more significant projects like Crossrail) or at all (eg MML
electrification).

Rail industry vapourware is rampant.
--
Roland Perry