I was using dodge windows in unity mainly because it make the launcher go out of the way on maximized apps (like Kdenlive who is benefiting a lot from unity's capability of making the most space usable). But I was never hiding the launcher when I use "windowed" apps (like firefox on the left and openoffice on the righ part of the screen) because it helped me a lot switching with something else rapidly (like thunderbird, pidgin, etc) What I think to be a good third behavior of the launcher is to hide itself when one app or more are fullscreen and if they are not, being always there. There is some corner cases like if one app is full screen and the focused app is not. But I think this will not bring some crazy bugs like dodging windows did in the past.