You could do it with IR if you had discrete IR codes for different lighting levels.  i.e. 0%, 20%, 40%, etc.  Then you could do different visible/invisible buttons by setting and clearing a bunch of flags.

Of course, this all goes out the window if someone turns the light on or off from the dimmer itself, or a lighting keypad, or from another scene, etc.  No way to track what's actually happening so it would really be a waste of time unfortunately.