There is a single sensor for the overhead distance. It is positioned directly between the falcon wing doors on the roof. Initially, the reading of this sensor would determine the height of the doors, and it would only do so in real-time -- that is, what it sees right now. That's the source of this thread. Things have changed since then.
Now, the system buffers the lowest height detected by the sensor for some specified distance. Once it detects an "indoor" space, the doors open in a relatively low profile, which appears to be independent of the specific ceiling height. For example, my doors can pretty much open all the way in my garage, but they do not. They open the same way they do when I'm in a parking garage. I know it's the same height because the corner of the door is right about at my eyeball, threatening to poke it out if I turn rapidly.
What does this mean for
@Tozla's wife? I am quite sure the sensor will detect that beam because it'll be directly below it (assuming she parks as viewed in the photo). I
assume the doors will open in a limited fashion and she should be fine. But I'd be very cautious if I were her.
If you hold the button as
@K-MTG said, it will go slowly and stop immediately when let off.
A note about the suspension - it doesn't stay in place between when the car is off and back on. Even if you geofence it. So be very careful about relying on that for door opening height.