Many thanks for your response. A few points:

My suggestion was in ignorance of this foolhardy idea
of pedestrianising Oxford Street. Does Westminster
Council really believe that making shoppers carry all
their parcels, even large, heavy ones, will persuade
people back to Oxford Street? That's counter intuitive,
to put it mildly.

Clearly, if terminating bus services at Marble Arch and
New Oxford Street is impracticable, those bus services
would have to continue to somewhere else. That's not
necessarily an unworkable idea.

Turning a trolley bus shuttle service around would not be
difficult if overhead cables are strung up all round the
Marble Arch/Cumberland Gate gyratory system and the New
Oxford Street/Dyott Street/St. Giles High Street gyratory.
Because such a short distance is involved, there would be
no need for "rest breaks" at the end of each journey and
no need to keep to a strict timetable, so buses would not
need to park up at either end of Oxford Street.

I didn't know TfL had an abhorrence of trolley buses. Why do
they? TfL has no experience of them because they were
eliminated when I was still a boy and, sadly, that was a long
time ago.

I also didn't know about the plans to sabotage Gloucester Place,
Baker Street, Tottenham Court Road and Gower Street. I'm not
at all surprised to find local opposition to this nonsense. I've
expressed my opinions in the past about TfL's motives for
changing roads and their love of conflicting traffic flows and
innumerable traffic lights. (David Cameron: you are so naïve)
The plan to return these roads to two way running will of course
be ruinous. I do hope the new Mayor's reservations about TfL
will prompt him to intervene and to replace the vandals at TfL
with responsible, public minded people.