It is hard to stabilize a system like that in the station-keeping phase, the biggest problem is that the two bodies form a swing, and also the transverse vibration. One time, the shuttle deployed a tethered probe, and orbiter and the probe started swinging and vibrating. Of course that time, the length of the cable was about 20 mile. MIT did some work on this system, and make them 3 tethered nano sats fly in formation. Don't know much details about it.