I wonder if Network Rail agree about the feasibility of 6 passenger
trains and 6 freight trains an hour. (Mind you, I've never seen any
evidence that there's a need for 6 freight paths an hour!)

I don't know how likely a cross Thames extension is, but I hope
it won't require much demolition of newly created infrastructure.

Don't know if NR agree or not. The operation of extra trains would require an extra freight passing loop - that's in the inspector's report. I think past NR documents have said that signalling mods would also be needed to run an enhanced frequency. However this isn't mentioned in the inspector's report.

TfL told the inquiry that it will likely be the 2030s before a cross river link could be contemplated or afforded. A cost of £1.2-£1.8bn is cited. One objector went to great lengths to try to discredit the elevated design as it would need to be demolished and replaced with a descending tunnel alignment and sub surface station if the link to Abbey Wood is built. The objections were rejected because forcing TfL to build a tunnelled link now was not in the current project scope / design, not funded and not within the pervue of the inquiry. The inspector said that if the elevated link eventually had to be demonlished then it would not be money wasted given that providing the link would have enabled the building of 10,500 new homes.

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Paul C
via Google