Just realised the design of concrete median dividers on the freeway reduces damage to the vehicle if somebody is unfortunate enough to hit one. It does this by allowing the front wheel to "climb" the median slightly in preference to scraping the side of the vehicle. Due to the shape, the wheel is the first point of contact. With luck this will alert you to the problem because you should notice the sudden change in level and you'll get out of it OK with maybe only a damaged rim.
UNLESS you hit one of these at speed. Then it's a guaranteed flip.
No I didn't find out the hard way. This was just the result of mentally reconstructing barrier incidents based on the scrapes and scratches that are present. Most of the scrapes go up the wall and come down a metre or two later, however I noticed the marks of a couple of presumed flips during my drive this AM. The scrapes go up the wall and right off the top edge. Poor buggers.