Earl Purple wrote:

Yes, the A12 does provide an alternative route to Docklands just as my
proposed extension of the West Cross Route would provide an alternative
link from the A406 to the A40 (other than the A406 itself). By the way,
much of Cricklewood and Harlesden are relatively undeveloped, and
there's a disused railway line that crosses through Gladstone Park, so
part of the space is already there (albeit not exactly the line I have
drawn).

The line through Gladstone Park is far from disused - it just doesn't
have any passenger services. It was at one point proposed to use it
for Heathrow Connect.

A semi-orbital service from St Pancras or a Goblin extension, via
Cricklewood and out to the west might well be useful, especially at
Olympic time.

Public transport loses out on journey time if the journey involves
more than one change. So the best orbital services go about a third of
the way round, overlapping with other orbital services, and continue
outward or inward at both ends of the orbital section. This maximises
the number of journeys that can be done with one change.

Colin McKenzie