dvenman wrote:Every drive on a frequent basis. I'm not keeping a constant 2 seconds but it'll get there in time.
Very well. How do you measure? that is to say, what do you use as a marker?
Using lamp posts as markers, for instance, is bullocks. We need to use marks on the road (chevrons, arrows) to be anywhere near accurate. The words one needs to use in order to count also need to be made of enough syllabels to ensure that the margin is measured properly, and it's a good idea to measure two times in a row to ensure that little bits of engine braking won't change our estimation of following distance.
As for maintaining a full two seconds: Reaction times measure broadly, as do stopping capabilities. So that a temporary 1.5 seconds margin is perfectly acceptable. On the other end, many drivers (typically not advaned drivers, though) would need three seconds rather than two, to be safe.