Perhaps if the feature requires continuous observation by the driver, it should require a continuous 'hold' of the button to operate?
Accepted a beta feature, disabled the safety override, ignored a warning, and failed to observe the car as he was told to;
It simply is operator fault. He can be lucky it wasn't one of these power drills with a "perma-on" button, which would've ended much worse for him.
I will admit that the first thing I did when I got the update that defaulted to dead-man's-switch operation was to put it back the way it was. But I was careful to understand the implications of what I was doing, at least.
In Australia, we don't have the option of disabling the dead man's switch, so we're forced to use the phone app to control Summon.
There are no words in the English language that can begin to describe how frustratingly unreliable it is. Most of the time it simply doesn't work (will say something like "failed to communicate with car"), and even when it does work it tends to lose connection half way and abort. I don't think I've ever managed to complete a Summon without it aborting. This is exacerbated by the fact that the places where I actually need to use Summon tend to be places with poor cell phone reception, e.g. underground car parks.
I can't wait for the key fob-controlled Summon to be enabled in Australia. Summon in its current state is basically useless.
It's too bad the phone app can't communicate directly with the car using local radio, like Bluetooth or peer-to-peer WiFi. That would solve this problem and others besides.