The problem with any adjustment is that he car can just pass from one view to another just between you refocus your eyes between them (ie. from rear to side mirror, from side mirror to side window). The solution is panoramatic rear view mirror (you can see thru the rear plus backseat side windows) and side mirrors with curved section that pretty much eliminate the blind spot
http://gmauthority.com/blog/gm/general-motors-technology/gm-...
Hope it catches on. Can't wait till it's on more makes/models.