Whatever the outcome of the re-bidding for the franchises to run trains, the East Coast Main Line is going to be Britain's only site 630km long and with a high speed train service running through the centre.
Variously there will be some 50 separate construction projects. These range from from rationalising antiquated track layout to new rail flyovers and rebuilt stations, all geared towards satisfying Railtrack's own predicted ten year passenger growth.
Enter the shadow Strategic Rail Authority, charged by government with analysing this jigsaw and determining overall value for money.
Enter also three consultants - transport planner MVA, civils advisor Posford Rail and train operating specialist Comreco Rail - appointed by the sSRA last December to conduct a six month 'due diligence' study of the plans.
'It is really a non confrontational audit on Railtrack's upgrade costings, ' explains MVA rail director John Segal.
'We will also separately analyse the TOC bids, though it is unlikely we will specifically recommend one over the other.'
The Railtrack work concentrates on removing bottlenecks and diverting slow moving freight traffic onto four reopened and refurbished loop lines.
Where there is no such diversion, the sections of twin track south of Newcastle will be increased to four track, creating, in effect, two twin track routes: one for passenger traffic and the other, via the loop lines, for freight.
Railtrack's upgrade is divided into four phases at a cost approaching £2bn.
Phase One is almost exclusively improvements to and around Leeds station, already under way.
Later phases include the upgrade of four loop lines for freight traffic; track rationalisation at Doncaster, Newark, Peterborough and Hitchin; four tracking of 14km of dual track on the route; and alterations to or rebuilding of 75 bridges and three tunnels.