I think you are slightly miss understanding the spring effector - its designed to add a spring effect to clones after they have been moved, so it makes sense to me that its behaving that way.
to get the behaviour you are looking for, i think i’d need to know the final effect you are going for. in the basic sample your showing, i would use math in sine mode, and maybe animate the falloff along with the blend amount. the spring effector might not even be necessary in this case.