Thanks for the one way suggestion and other contributions. My worry about a one way system is it speeds up the traffic, having just achieved a 20 mph zone. It seems illogical to me that cars park on the pavement, presumably so the road is then wide enough for through traffic to go fast and past each other at speed, while trying to slow down the traffic with a 20 mph zone.
I did write to the mayor before we knew the 20mph zone was proposed, about local traffic, speed, crossing on Honor Oak Park for one tree hill etc, bus stops without bus shelters and he describrd my letter as a 'dirge'. I sent copies of it to our MP who didn't reply, and I had a discussion with Simon Feakes while he was canvassing about a 20mph, only to be surprised a month later, once the consultation was out, that he gave an interview in the South London local papers saying the residents of Forest Hill did not want the 20mph ( without waiting for the positive result!)
It seems to me there is no political will to address such issues meaningfully.
My suggestion of the blocking of Devonshire Rd is just based on what I see at Grierson Rd, a rd parallel to the railway, as wide as Devonshire, and as potentially busy as Devonshire Rd (motorists could turn off Brockley Rise to miss out the traffic lights ect and Vice Versa), but which is not a rat run ( I'm talking about where it joins Honor Oak Park by The Old Bank Restaurant).
I'm no expert on solutions but I do think there is a problem.
Any other suggestions?