Not if you are just backing up with your rump you can back em underneath the rim or til they fall down til your hearts content... but as soon as you start putting your shoulder into em that's an offensive foul. Watch Kobe post, he does it the right way and never gets called for an offensive foul and nobody even bothers flopping cus they know they won't get the call. Watch Howard post, he does it the wrong way and gets called for it sometimes.
When faced with someone attempting the super power backdown, I'd recommend pulling the chair a time or two (i.e. stepping away when they blast in looking for contact). If nothing else, it may cause your opponent to back down with a little more care: http://www.youtube.com/watch?v=C9COZcS_v0c