Mmm, well Kwackers, you right to highlight a slight discrepancy, if only because the petition does seem to call for a blanket 20 limit and we've all been arguing for 20 with signed exceptions. I myself have never argued for a blanket 20, believing that it would prove unworkable, politically and practically. But I think most people on this thread have argued for 20 limits in residential areas town centre areas or main roads where there is a high volume of cycle and pedestrian activity.
The CTC response to the DfT consultation is in line with this:
"
How can we most effectively promote the implementation of 20 mph
zone schemes in residential areas? What other measures should be
encouraging to reduce pedestrian and cyclist casualties in towns?Making 20 mph the speed limit in ‘town of city streets… where pedestrian and
cycle movements are high’ (p. 52) is a very encouraging step. However, there
has been a lack of consistency in the message that all urban streets where cycle
or pedestrian movements are high should be considered. As in the phrasing of
this question, this has too often been contracted to just ‘residential areas’.
We also suggest that restricting advice to streets ‘where pedestrian and cycle
movements are high’ may mean that streets where cycle and pedestrian traffic is
suppressed by high traffic volume/speed will be left out. Thus a key route may
have low cycle usage because of concerns about dangers on the route from fast
moving traffic. Lowering the speed limit may encourage more pedestrian and
cycle usage, but under the suggested policy would not be prioritised.
We believe this would be better undertaken by a wider move to making 20 mph
the default urban speed limit, with local authorities varying the speed up to 30
mph on roads which are predominantly used for traffic movement, and where
accessibility by physically active modes is not compromised. Such an approach
would be far less costly than that proposed and has been successfully trialled in
Portsmouth.
The Department should allow a relaxation of the requirements on local authorities
to implement both 20 limits and zones – both are over-prescriptive."
The full CTC response is here
http://www.ctc.org.uk/resources/Campaigns/0907_CTC_A-safer-way-res_con.pdf