There is a manual overide switch on the module installed in the boat, so you're not dead in the water if your partner is out in the water with his sensor. But with that being said, I would still want full boat and motor control if he does fall out, instead of just shutting down cold. If you are in a large boat where you cannot keep your eye on all the passengers, then I can see the point in rigging everyone in the boat with one. The C.A.S.T. system is a pretty neat idea, but I think they've got an uphill battle in getting us bass boat guys to cut that little cord.
--Casey