Clovers come in more than one form. An especially aggravating form of Clover is the type that exhibit the following behavior:

You are on a two-lane road. Up ahead is a red light. There is a car already stopped in the right lane - and another car (the Cover) slowly coming up behind him in the same lane. You are the third car approaching the red light.

Just before he gets to the red light, Clover will pull into the free lane and come to a stop at the light next to the other car. When the light turns green, Clover will match the speed of the car to his right, preventing you from getting by or going faster.

Since Clover's not interested in going faster than the car next to him, why did he have to pull into the open lane at the light?

Because he's a Clover!