Bringing this back on-topic, tailgaters are one of the biggest reasons you'll see the yo-yo in the left lane. Someone is going too slow in the hammer lane, someone else tries to push him go to faster by tailgating, the slow guy slows from 65 to 55, the tailgater slams his breaks, taking him to 45, the guy tailgating the tailgater slams HIS breaks, taking him to 35.
Just weighing in on this very therapeutic thread and arguing some cause-effect
Wouldn't the original cause of the yo-yo'ing be the the ones who are going slow in the speed lane? The tailgaters are just the first ones affected by their disturbance of the system. They certainly exacerbate the problem by riding too close, but the obstacle is the slow-roller in the inappropriate lane, so they would be the reason for the yo-yo'ing.
Democracy is the tyranny of the majority.
Bus error -- driver executed.