Douglas Steel wrote in
:

Martin Underwood wrote:
I would never try to race ahead of cars, because I know they'll only
catch up with me after a few yards, and I don't want to cause an
obstruction to them.

You sound like a timid and/or weak cyclist. Any reasonably fit cyclist
will be well away from the lights when they change to green before 90%
of motorists have started moving. Why should I delay my journey
unnecessarily just because a motorist *may* eventually catch me up ?
At most traffic lights I encounter when cycling, the motorist won't
catch me up before the next queue of traffic anyway.

I agree that a fit cyclist probably has a faster 0-15 mph time that a car [*], but after that the car will catch him up and then, if the road isn't
wide enough to overtake, will be impeded from going any faster. Any vehicle
which cannot achieve the legal speed limit for the road (assuming it is safe
to drive at that speed) is likely to cause an obstruction and should in an
ideal world be segregated from the traffic that can achieve that speed.
Where that's not possible, the next best thing is for cyclists to keep
left - except when they want to turn right at a traffic lights, when I agree
that a cyclists' refuge ahead of the car stop line is a good thing.

[*] Assuming that the cyclist hasn't made the elementary mistake that I
still occasionally make, forgetting to change down while approaching the
junction because derailleur gears don't like to be changed when you're
stationary - the complete opposite of driving when advanced driving
techniques say approach in a moderately high gear and then select the
correct gear to accelerate out of the hazard at the point where you decide
which is the appropriate gear. I spent so long training myself to do this
for my IAM test that I sometimes forget not to do it when riding my bike!
Very embarrassing and I'm sure drivers curse me!