This states it far more eloquently than I can:
http://www.silive.com/northshore/ind...ts_when_s.html
"
Traffic scientists can only agree about the ideal scenario, where the rules of time and space yield so obedient drivers slow down, fit nicely into the next available lane and then elegantly glide through a work zone as if in a well-timed waltz.
"
To wait until the last moment and muscle your way in is inefficient," said Doug Hecox, a Federal Highway Administration spokesman. "And it's a risk to the other motorists who have to stop and give way."
Unfortunately, Hecox said, local conditions and human fallibility mean each situation warrants a different solution."
