>"The vehicle will continue running in perpetuity until it runs out of gas or until you shut it down," he said.
>"They do that for safety so that if you lose the key fob or if it loses signal the vehicle doesn't shut down while you're driving, but that right there is part of the vulnerability."
Anecdata, a few years ago my wife had a Renault "Megane" that used a sort of "card" that worked with proximity.
She opened and started/drove it without ever taking the card out of her bag.
A couple of times I was driving it with her in the passenger seat, we arrived to a shop, she got down in front of the door and went into the shop while I was going to park it when the car some 20-30 mt away "locked itself" (cannot remember if it stopped or just didn't allow more than - say - 5 km per hour) with the display saying it couldn't find the card.
When she changed cars, her new Renault (using the same kind of card, at least visually, but a different car model) had to be inserted in a slot to allow the Start/Run button to operate.