A couple of thoughts. First this can only occur if there is movement or flex. If the control arm bushings, idler arm pivot, or strut rod bushings compress and release you will see positive/negative toe change. Additionally there could be hard part flexing. Control arms, tie rod sleeves, ball joints, and even uni-body. So what gets all this started? My feeling is as the A-arms pivot downward and the front of the car raises, the track becomes narrower. When the tires return to the track surface they are being forced outward trying to return to the static track width. This part of the geometry we can not change. Good condition parts, poly bushings are the first step. My bet as stated earlier is the idler arm pivot bushing is a big factor. Tightening the compression on the front shocks helps by slowing the return to earth. I know mine has done it it on occasion when the shock settings are to loose. Look at Tigs car in the video. The RF is wobbling on the way up.
Doug