I don’t know when I’d want to use this over a dive propulsion vehicle. Not kicking at all will reduce oxygen use even more than machine assisted kicking.

I guess it leaves your hands free while moving, but with similar amounts of engineering effort you could mount thrusters on the user and free up their hands too. I think DPVs are partially used as separate devices for safety though.

Oh this is like the ones they have for climbing for tourists, I wanted to try those out if I ever get to visit.