Explanation time.... (I thought my knowledge of company finances would come in useful)
In America, there is 2 types of Bankruptcy, Chapter 7 (more for individuals) and Chapter 11. When a company goes bankrupt over there, they apply for Chapter 11 (same as going into administration over here), which means they company is re-organized in order to pay of it's debts. Sometimes this just means changes in the way the company operates, but more often, parts of the company are sold as going concerns (IE, Sea Containers selling GNER for example). The money raised from that go towards paying of the debt (and associated court fees), but the company sold carries on as normal. So all this "should" be no changes on the ECML (other than a probable name change).
Guess we'll just have to see what happens. GNER have admitted they have struggled since it was given a 10-year extension to it's franchise, so the DfT will be keeping a close eye on them even more now, & if they put a foot wrong, they'll be out. GNER are already starting to restructure it's services to cut costs, inc. doing away with the waiter service on it's trains, they're the last TOC company that has waiter service I believe.
how about making the trains longer so they can sell more tickets without faffing about with extra route charges, perhaps this extra supply can mean the fares can go down making train travel more popular and stop charging over a tenner for a fry up in the restaraunt so someone would buy it!
It could be implemented on any train, even HSTs (just have to be able to select which doors to release), but it would cost money and need a lot of work (probably a near total replacement of the CDL or door control circuitry). It's not been retrofitted to any trains, but that's because it's never been needed (since they have "grandfarther rights" to stop at stations that are too short) not because it can't be done. There are other issues aswell though. Especially for the Mk4s, stock availablity is an issues, I doubt enough Mk4s are spair to extend existing sets even by one coach. Also, adding extra trailers reduces performance, and this can make capacity issues worse. The 91s, arn't special when it comes to performance anyway (they lack tractive effort and raw horsepower for starting, due to low weight, and actually are slower off the mark then HSTs, and way behind modern units like 22Xs). You've also got problems of long trains fowling junctions etc, although since regional Eurostars ran on the ECML that can't be too much of a problem, not to Leeds anyway.
The regional eurostars couldn't operate to Newcastle and beyond as they would have got stuck on the S bend south of the King Edward Bridge. There has been a 10mph "temporary" speed restriction in force for some time because of the severity of the curve.
I'm not sure if the exact cause is overall length, coach length or a combination of the two, so its possible that longer rakes of mk4s wouldn't be able to make it round.
AFAIK, the main problem with the Eurostars was the distance between the bogie centres which was higher than normal due to the articulation, and this lead to very low clearance around the curve south of Newcastle, and this mean that the dynamic envelope was such that there was a big risk of trains coming into contact with each other. In fact, the tests also highlighted the fact that the dynamic envelope on other trains didn't have enough tolerance (railways usually like 10% tolerance to take into account overspeeding, track and train faults etc), so the speed was reduced for all trains to deal with this. By the way, dynamic envelope refers to the space that can be occupied by a train (or any other vehicle) when travelling at a particular speed, taking into account that it's not fixed rigid to the track due to the suspension etc. It's like how when driving a car, if you go over certain road features like speed humps at too high speed the suspension will be compressed to the point where part of the underside strikes the road, wheras as normal speeds this would't happen.
Nobody made them bid that much. Since franchises tend to be done on the basis of the highest bidder winning, if the TOCs think they are too expensive they should put lower bids in. It's like going to an auction and blaiming the auctioneer because you ended up bidding more than an item was worth. The only people to blaim in these cases are the fools who are prepared to pay silly money for things that arn't worth anything like it. GNER might argue that they put in a bid expecting to have the extra paths for Leeds trains, but unless there was a guarentee that they would have the paths, they should have made the bid based on the current level of services they could run, not a possible future service level.