Clive D. W. Feather wrote:

The Jubilee would have been better continuing from North Greenwich to
North Woolwich and Thamesmead. But, TfL are awful fond of their DLR
toy train system.

Provision has been made for this: there are junctions at the north end of
North Greenwich station, though without track on the east-facing arms. It
should be possible to build a branch that way without disrupting the
existing service during most of construction.

However, I suspect the demand for service to/from Stratford means you
couldn't afford to divert 1/2 or 1/3 of the trains elsewhere.

A number of services terminate at North Greenwich so they might become the
nucleus of a Thamesmead service. However I don't know how separated the
junctions would be. And I suspect the demand from such a branch would be too
heavy.

For such a modern station North Greenwich is badly laid out with the
terminal platform (which would become the Thamesmead bound one?) sharing an
island with the Stanmore bound platform. This makes it a bad station for
changing trains onto a Stratford through and announcements promote Canary
Wharf instead. Having the island on the other side or having a platform on
both sides (with the doors actually opening both sides *) would be much more
efficient.

(* Looking at you Barking and Norwood Junction.)

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