Thanks to the efforts of sydinstaller I better understand the inheritance settings and the influence of the "Site Map View".

I make a simple page collection with which I simulated the effect of
the inheritance on the "Site Map View" page. Than you can see what the influence is of inheritance.

I see the default setting is "Yes" of the inheritance .

It is in my view agood starting point for a discussion with other people
about houw to handle the inheritance settings in their configuration.