driving in a near straight line
 

or the best line.

ok if you drove your car on the motorway whilst sticking to the best line.. so if the rd bended to the right you would move the car to the 3rd lane and if it veered left you would move your car to the first lane

providing the roads were all quiet so u werent upsetting anyone

wud u save much distance if u say drove normally, or just in the middle lane or indeed the opposite of best line?