In my routine I first let the spectator do several cuts while the whole time there is one pair of magnets inside the rope (yes I have to do the gimmicking for each performance).
I'm wondering what the reasoning is behind that move so that it looks normal to the spectator. Sometimes magicians are guilty of putting in extra but unneccessary moves to disguise the sleights which results in the handling not being of any real sense to the audience. I'm not saying that this is such a case as it's difficult to tell from the post to date.
However, I'd recommend that you check out a routine called Roped-In by Joe Riding, available in manuscript which you can get from
http://www.mikedanatasmagicstudio.co.uk. It's a lovely cut and restored routine that's full of audience participation and no magnets are needed.
Member of the Magic Circle & The 2009 British Isles Close-Up Magician of the Year
It's not really an optical illusion - it just looks like one!