Also, if Manchester goes to 2tph, and therefore Stoke - then both MKC and Macc calls are on every service. Which slows it to 2h10 minimum. Assuming Wilmslow is preserved - thay might be able to take a MKC (but it will/should have the Chester for that).
If Manchester didn't justify more than 2tph from London in better times, HS2 2b would not really be a going concern.
If it's the SW/NE going to Moor St, who keeps their direct Manchester, Reading or Bristol? Presumably Bristol would have 2tph headed to Derby?