Sorry, why in this scenario would it have the same rolling stock as today? Wouldn't it get new HS2 stock?
Because they wouldn't go anywhere that requires it, and the trains would be empty. The whole idea of HS2 to Leeds / York / Newcastle is they can go to Euston. A Leeds to Birmingham New Street / International route couldn't go to Euston because of capacity. So either it's a shuttle to Leeds and Back, or it would just be the existing Cross-Country North East arm using HS2, which needs to go to off-wire destinations.
A Manchester to Birmingham to Euston link could work, and could justify new trains (although Euston wouldn't have the platform length to accomodate them). But as I say, it'd run at the same speed to Birmingham, and then by the time it accelerated and slowed on its way to Manchester, what exactly have you saved over a Pendolino? 10 minutes? 15?
NPR / HS3 would make more sense to build first than phase 2b of HS2 on its own. Nothing to do with "the North", just common sense.
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A 2 year delay is disappointing, but in all honesty not surprising. From a Treasury point of view this is a HUGE project, probably counting for a significant proportion of the national GDP. If inflation reduces over the next year or so, they can sign contracts at a lower price. Or they could sign contracts at a higher price today which not only is affected
by inflation, but would
contribute to inflation due to the vast amount of money expended.
Compared to some schemes, we're still not doing too badly. E.g. Heathrow Runway 3 (under discussion for 20 years, not even approved yet); Stonehenge Tunnel (under discussion for 30 years, not even approved yet); Mottram By-Pass at the end of the M67 (under discussion for 60 years, approved nearly 10 years ago, no spade in the ground yet).
NIMBYism has an institutional chokehold over infrastructure in this country and allows schemes to be kicked into the long grass time after time. I'm not suggesting we should necessarily go the Chinese way i.e. "we decided last week we're building this, get out of your house as we're knocking it down on Tuesday". But there's got to be a better way. Neither of the two main parties has any interest in changing things. When I was born, 40-odd years ago, the population of the country was 56 million. We're probably over 70 million now, and the only major infrastructure differences over that period of time is HS1, some regional railway electrification, the M40 motorway and a few road widening schemes and smart motorways. For a population that's one quarter bigger.