The main issue is that it relies on drivers themselves sticking to the new limit to smooth traffic flow.

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The plans for the motorway near Sheffield include variable mandatory speed limits displayed on overhead and verge-mounted signs to smooth traffic flow and reduce congestion said the agency.

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Other transport projects anticipated this year include work on a new Isle of Dogs Crossrail station, "intensification" of the work to extend the East London Line and a host of initiatives to help smooth traffic flow.

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In theory, drivers will then adjust their departure times and smooth out the flow of traffic through the day.

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