I will have to go with the majority and say the double lift. Not only is it probably the most important, but the most DIFFICULT sleight to perorm. Yes, I said one of the most difficult to perform. There are loads of sleights out there that, even if you were a professional magician, you could not see anything not normal. Palms, Passes, Side Steals, Bottom deals, Second Deals, Center Deals, Convincing Controls... the list goes on.
But any magician, even a beginner, can always tell when a double lift has been performed.
My view may be wrong, but the only time I know I can do a certain sleight is when other magicians can't see me doing it. Simply because I perform to other magicians 80 percent of the time.
Never have I seen a trick where I have not spotted a double lift, even Paul Wilson's Ultra Natural. I know people will disagree, but it's just an opinion
