Course titular default is platform admin
When a course-administrator creates a course, by default the platform-administrator is selected as titular. This means the course-administrator has to go through the list to select himself as titular.
If he doesn't do this, the platform administrator becomes titular of the course and is also added to the course. The result is that the platform administrator gets a lot of courses in his list....
There is no setting where you can influence this behaviour.
I tried to search the code but apparently there are a lot of changes going on in the structure of the application, meaning there are a lot of dead files not used any more. I found the course_setting.xml now is defining the settings-form an the default id for the titular is set to 2. But the default id for the titular of the course should be the course administrator himself.