So let's see if I get this. What you are basically purposing is that there is a reserved area where the normal kinetic operations are turned into scroll operations? Kind of like how some trackpads on laptops have a special area for scrolling verse mouse movement? So its not a full traditional scrollbar and does not cause application interference anymore than kinetic scrolling does. I find it interesting. The main concern I would have is discoverability. Users might just perceive it as arbitrary/random behavior I guess it would also cause issues with users having to care where they do their kinetic swipes.