Had a closer look here, and some observations, there is quite a bit of KPN in the stroke.
The intermitant funny arm recovery is likely on breathing strokes
the pulling arm doesnt go back as far in order not to sabotage the front arm when breathing,
"in order for the lead arm to support the breath the pulling arm cant go back too far"
Its likely she putting the "umph at the front" and using a brief power tap and releasing the pull early, letting the arm wash back and flowing into the straight arm recovery pinkle out around waistband area.