That is - straightening the roundabouts when they aren't too busy. Time will come a young man ... it's just going to be illegal to drive once the machines are safer than humans. Then we can just blow thru the intersections at 40 because the cars will make slight adjustments to barely miss each other. Will save the planet too, all the energy that will be saved, darn inertia anyway. Then we'll wonder why we spent so much on roundabouts, like building a nice canal in 1830. Or HSR in 2020. [There's two rail references.]