Once Old Oak Common is open, I suspdct it may become busier than Pad eventually...have to wait & see
Hmmm ... it's the number of trains that's the issue here, so you would need to stop and start trains at
OOC▸ to have any effect on that. Assuming it has only through platforms, you need to take trains out to prep them, and OOC is just about the worst possible place to do that from.
But seriously, Network Rail in the Western Route Study concluded the capacity pinch was on the twin line out to Airport Junction, and after
ERTMS▸ arrives it's the bit of plaiting from Ladbroke Grove inwards to spread trains over all the platforms. While they mention the need for platform capacity to cope, they don't propose doing anything about it. OK, they would like to get rid of Heathrow Express, but that's not their call.
The one thing the
TOC▸ is responsible for the is turn-round time, which no-one has mentioned. With 16 tph (post-Crossrail line limit, subtracting 4 HEx) and only 8 platforms (roughly as now) there is 30 minutes per train including all allowances for getting in and out. If there are even three more platforms, that become 40 minutes. That sounds enough, given that there will be no paper reservations and window posters to fix.
If, longer term, you could get
NR» 's Ladbroke Grove flyover and evict HEx, that would be 24 tph in 13 platforms: 32 minutes. That doesn't sound impossible, for a well-organised TOC.