I've done it twice to get rid of ick with just live rock and fish in the tank
and it has worked great both times.I would also do the fresh water dip also to kill off any ick that is on them.as far as the live rock I didn't have any problem with it coming back as long as there are no inverts or coral on it.
it took about two weeks with the salt at 1.013 and the ick cleared up on the fish although they say to keep it that low for about 4 weeks to be safe.
hope this helps.
also here is a link that has good info on it and other things.
About Saltwater Aquariums - Reef Tanks