After cycling through for months, I finally did some clean-up of the map around Südwestkorso. It's one of these typical Berlin dual-carriageways, in this case with parking down the middle. From the aerial photography, it's quite difficult to make out how it intersects adjacent residentials, in particular at what points you can cross the middle strip. These details were very much wrong. Furthermore, a few neighbouring one-way streets were missing. I do wonder how the street names were obtained.

I'm guessing a lot of the dual-carriageways in Berlin need similar clean-up with respect to intersections.

The fact that I travelled through countless times without realising there was work left to do does give some credit to the opinion that aerial mapping without surveying is evil. The map just looks too complete afterwards. But there should be better ways to show incompleteness than not mapping at all.

By the way, having the map in front of you on your GPS makes it a lot easier to spot such mistakes. I doubt I'd have noticed just from looking at the slippy map.