I'm passing quite often one of these borders supposedly with controls and the cars are waved through by the officers. Even better, if you are passing the border on foot or on a bike, there are no officers to be seen at all. So the controls are nominally reintroduced to score some political points, most probably.
Yeah, this been my experience as well (in South/West Schengen, by car). I've seen spot checks more regularly though, compared to some years ago when there was literally nothing.
