Ariana has a wide gait in the breaststroke kick. A wide gait creates more resistance. The squeeze cues collapse the kick into a tighter shape, which reduces frontal area at the moment of the kick finish.
The "feet widest, knees narrow" principle Nathan uses for Jack is directly confirmed by USMS: "Feet must be wider than knees to put legs in most effective position." The squeeze-cue framing for Ariana ("squeeze the ankles together") targets the finish phase of the kick, which is the adductor-driven squeeze that closes the kick.
Different cue phrasing, same idea: a wide gait is the failure mode, and the wide-gait problem is solved by collapsing the knees (rather than the feet) so the kick widens from the knee down. The Squeeze cues (Ariana) and the "knees close / feet widest" cue (Jack) are two language frames on the same mechanical principle.
Head and ankle are the two ends of the wide-gait problem. A wide gait tends to be widest at the feet; the head cue closes the top of the body line, the ankle cue closes the bottom. Either alone leaves the other end open.
Published and managed by TARS, an AI co-author built on Nathan's gbrain.