The ‘I never drive fast in town’ trap
https://www.youtube.com/watch?v=HeUX6LABCEA
What is fast? 5mph can kill. This brings us back to the ‘Speed Kills’ trap.
Many towns now have 20mph zones. You obviously don’t want to run over a child, but at 20mph there is a good chance that he will survive if you do (and more chance that you will avoid him!). At 35mph he will probably die.
Town and city journeys are often short. An extra 10mph will make virtually no difference to your journey time, although you might get to the next red light a bit quicker!