The idea
Remove the law stopping overtaking on the inside on motorways and make all lanes on a motorway equal as is currently done in the USA and other countries. This will remove the need of many people to constantly hog the "fast lane". Any argument against this on the grounds of safety is now defunct as so many people flout the rules and overtake on the inside anyway that it is impossible to move lanes in either direction without a thorough check that the lane is clear. With no one lane being thought of as the "fast lane" then all traffic will spread out evenly and traffic will flow much more freely.
Why is it important?
Congestion is an ever increasing problem that only get worse and worse. Emissions from cars are increased with cars queueing and stopping and starting constantly, fuel reserves are being used up unecessarily and tempers get frayed leading to road rage incidents and bad driving. The problem is worsened by a large proportion of drivers seemingly unable or unwilling to use the "slow lane". Almost every time I drive on a motorway when it is busy there is a stream of traffic stopping and starting in lane 3 whilst very few cars are using the "slow lane". This may also help to eliminate the serious speeders as all lanes should travel at a more constant speed and may restrict those wanting to hugely exceed the limits.