Distance objective has an effect even when far from radius

[SidneyBovet]

Given the setup below, where I have two IK chains of a number of segments each, I am trying to get the two chains to avoid each other. I (programmatically) set up distance objectives for some of the joints in the chains but, as you can see, even when farther away than the objective's radius, they try to avoid one another:

I know a distance objective is no collision detection system, but is there a way for it not to have an effect on the IK computation unless the segments are about to touch?