So the sentry gun operates without a supervised person, so that you do not get over shot.. cool.. I Pity the FOOL.. haha
We operate it supervised - for safety reasons. But it thinks for itself.
If you have an accident though we do always have someone supervising to disable it.
The sentry is in full control - you move into its line of sight, it will track you and intelligently aim depending on your movement. It will keep shooting while you present a target, it won't stop because you call hit or put your hand up. It will also pick multiple targets. (And take your photo as it shoots you)
I did manage to begin to beat it once trying to be sneaky while two others ran around - a partial success as I could not move and every time they crossed over me it would chase them but pause to put a couple of shots on me as it passed!
The way to minimise being shot, other than not going up against it, it to plan your escape - either keep to boundaries so you can duck out or keep on running and dot head straight forwards.
For some tips on how to distract it watch the segment online.
Though there was the magic of television involved the techniques did work. However you need everything to work every time and for you to beat the AI. What it does not show you is how he got the neck wound you are shown at the end.
When preparing to film the director did not want Joel to experience being shot as he had never played paintball and he wanted a genuine reaction. It was for late evening TV so language was not an issue - other than 2 specific words.
As action was called as soon as he moved he took a burst of 3 shots that went across his neck, and they did not break. 2 specific words echoed across the site giving un-televisable footage.