Generally, if the tyres are correctly inflated, you stay on the pavement, and don't hit a pot hole or kerb then you should stay upright. If something happens to 'trip' the car, as was the case in the wheels test, then it's a whole different story. Deliberately attempting to put your vehicle in an unstable situation under uncontrolled conditions is extremely stupid, especially on a public road.
Hope your not suggesting what I did was on a public road? And what are "uncontrolled conditions"?
I was more getting at how it's not an easy task using the footbrake to get it sideways compared to using a handbrake.