Not really as there a risk factor of putting new pans onto the older stock. Who bares that risk along with increased costs you proposed?
What 387 failed on AC/DC change over? I'm not aware of any.
What premium? there is no such thing for the TSGN franchise. They are paid for what they provide, end of. Seems you need to brush up on what's actually going on.
You've failed to address whom picks up these extra costs. Using Old Dalby to simulate City - Farringdon would have limited benefits. Not least because none of the 387 failure have occurred there of course.
And ups the risk which always costs extra money.
The froth is your claims of issues at the AC/DC point.
Care to show where costs have been cut please? Thameslink isn't a Underground type service unless there is an unknown Tube line with 2tph frequencies. The only place its like the Tube is in the Core section for now. Of course St Pancras to East Croydon will Tube like frequencies come 2018.
Why should TfL be running services to Peterborough, Cambridge, Bedford, Littlehampton and Brighton? TfL don't know how to run a mainline railway, that's why they employ others to do so. TfL set standards not operate railways. f course comparing the Overground today with Thameslink today is unfair as the full investment hasn't yet been seen as all Thameslink has seen is 2 and a half stations built and lots of ground work done. As someone who used the Overground at the same stage as Thameslink is now, its wasn't all roses and still isn't now.
I think you need to actually read up on the situation because you seem to bring up the 387 issues on AC/DC changeover yet their issues aren't in this section at all. In fact the 377 and 319 fleets still have occasional issues suggests your idea of ironing out all the bugs is misplaced at best. Ultimately you seem to be attacking Thameslink as a whole and confusing the discussions on the 387s and their faults with how you mistakenly seen the TSGN franchise.
I'm not going to line by line the above process because I have not got time however a couple of points.
1) I'm not attacking Thameslink specifically, I'm attacking the whole franchising process which encourages short termism and minimising costs to win the franchise on a competitive basis (by having lower costs than your competitor and therefore can undercut them), all of which are detrimental to quality.The weakness of the franchise system particularly manifests itself on something like Thameslink, due to the high service frequency and huge number of pax with two way flows and multiple conflict with other networks on much of the route.
TFL type management contracts where the company keeps none of the revenue and are paid to provide a service, and heavily penalised or chucked off if they don't, and the management company invisible to the public with trains and publicity in the owners livery not the management companies livery, are far better. However I simply don't trust the DfT not to *** it up, and think it might be better if TfL were in charge and set the management contract.
2) I'm not suggesting using Old Dalby for just the a.c. d.c. changeover, I'm suggesting it is used for all aspects of running, high speed and low speed a.c. and d.c. and changeovers. Only when it has completed a certain amount of mileage trouble free should it be allowed in service. Yes it would cost, but I'm fed up with suffering the cost of non quality when I try and go home.
If the liquidated damages imposed on the franchisee for such failures were high enough, then they would have the incentive/business to pay for testing which replicates all aspects of service for several months at the 20 mile long, electrified, Old Dalby test track before letting new types of train loose, so ultimately imho this is down to the DfT not making the franchise contracts robust enough - probably because the franchisees would put in higher bids if they did.
With concessions the DfT would be hit in the pocket by non quality because crap service lowers revenue, which with a managment service would go to DfT so DfT would have more incentive to put robust conditions of the type I outline above in place with a management contract.
3) The difficulties of fitting pantos to 377s seem to me to be being exaggerated. They are designed to have them so it is a routine low risk operation to fit them using standard parts. (but obviously test them first before letting them loose).