I somewhat disagree with Joe. I end up playing with the spring tension (either with the spring peg in which hole, by bending the spring and/or by respacing the pads to change the amount of arm travel) on many repairs. Some of these repairs had gotten new cables. By the point I am centering the brakes or setting the lever pull amount the cables are freely moving.

I attribute this to Shimano's pursuit of less lever pulling effort, by the rider, as their goal. Most all the other manufacturers follow the Big S like lemmings. Combine low tension springs with designs that have little range of travel (when tensioned) and poor rim width and pivot boss locations and sometimes it seems like there's barely any spring tension at all and the lever rattles in it's body from a lax cable. Andy