Top Level Menu (Route) Called "Constantly"

Hi,

Trying to update a currently working plug-in, and I notice that it seems like the top level routine / route is called each time there is a call to the plug-in, even for lower level items. For example,

/video/myplugin -> gets called even for /video/myplugin/myfiles (myfiles also gets called, secondary)

Is this supposed to happen? It seems that only the lower level item should be called, once at that level.

Thanks!