"Now, I haven't tried it with anything BUT a mouse but wouldn't a controller be slower/less precise? (please guys, don't start anything) Still, I'd imagine it would be a lot better for my wrist *tear*."
The way the controller works is that it's "anchored" to the center lane. That is, if you don't move the stick it stays in the center, if you move it right, it switches over the right lane and vice versa and when you let go it centers itself again. It works quite well. However, moving your thumb around is slower than flicking your wrist, depending on your sensitivity settings.