But in general social mobility - although usually measured by the relation of the social status of parents to children, not within the live of one person - tends to be higher in Germany than in the US. I found e.g. this report as reference.

The possibility to change the path of your career later in life is really not so good.

One thing in defense of a splitted school system. Some states have as well unified schools, but the result is a huge boost for private for profit schools. For social mobility as measured above - intergenerational - this is very bad. To make some concessions to the existing social structure, but keeping the 'upper class' in public or non-profit schools, at least gives worker children the chance to visit the same school as the children of better off parents.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers