Very interesting stuving.
If they are really looking at a fairly radical change to service patterns, plus new stations and extra platforms to improve connectivity then it rather makes a nonsense of HS2▸ with it's 4 separate terminal stations. I suppose they could bring a train from the North into Curzon Street with a cross platform change into a London train. But that seems to defeat the objectives of HS2 of givng high speed journies to London from the North.
I suppose New Crewe is HS2's answer, I'm not sure Toton or Meadowhall meet the criteria.
New Reading with the flyunder from the Southern and the Viaduct and Festival lnes to the West with most lines bi-directional could with clever timetabling/platforming give some cross platform interchanges. Although like Salisbury you'd have to work out what flows to cater for. Heathrow (if West link is opened) and Gatwick from anywhere West. TV Crossrail stations to FGW▸ and Cross Country.
Not at all. If you look at HS2 as all an overlay express service, it might not need to take part in this connectivity stuff at all. Certainly you could argue that it should, and connections with local trains are important, but that would only involve a few HS2 services.
This is something implicit in this connectivity concept, though not spelled out. If there are 2 tph (typically) on the main lines that do connect, and the rest are express overlay, can that be reflected in their stopping patterns and the way they are sold? That is, drop the idea that all trains can be expected to connect with others, and label them as something like "connecting trains" and "direct trains"? One of the inherent trade-offs of the concept is a (potential) loss of point-point running speed, plus needing to change trains, which get offset by shorter connection times.
Mind you, I've always thought this fixation on HS2's termini as missing the point too. If you think of it as trying to add a more express capacity as a new pair of faster-than-fast lines, and then conclude that it is impractical to put them next to the old line, you need a new route but could still could try to expand existing stations to take all the new trains. But that's going to be very difficult (read expensive), and a lot of this capacity is used by people who really do want to go between London/Birmingham/Manchester etc. and jump in a tube/tram/taxi. On those grounds it makes sense to run trains between new city stations for them. By all means complain about poor connectivity, but don't ask for all those direct trains to be added back into existing, hard-to-expand, stations.
As for Reading, I suspect there is too much going on there for the concept to work well. So far, proposals for new through services on the relief lines (e.g. Gatwick-Basingstoke) have been motivated by lack of capacity in the new platforms 12-15 (already!). I know the rubric for the study was "start with a blank sheet of paper, see what timetable it leads to, and then work out what new infrastructure that needs", but "expand Reading relief side" is probably the wrong answer for the foreseeable future. But it may still be possible to make some improvements within the existing capacity. You really do need to work through the process to see!
Note that I am not trying to summarise the whole report so you need not read it.