Edit found this:I just washed my car parked on this driveway.
View attachment 784407
It didn't budge an inch.
IIRC when I first got the car I did the long press on the stalk, but either I read somewhere that it's unnecessary or I simply forgot about it and for the past year it's been parked there without the long press. Not sure what additional braking is needed if normal park stops it from rolling down that drive
Using the parking brake
I accidentally applied the parking brake doing about 50. A noticeable slowing down and a warning on screen. Meanwhile I'm still not sure if I need to apply the parking brake on the level when I park :). I'll see what appears on screen if I don't and just let the car apply it. When I use it...
teslamotorsclub.com
No definitive answer for what the long press does (other than in an emergency). No reports of the car rolling away with just the short press.