Trevi Fountain in Rome

Legend says that if a visitor to Trevi Fountain tosses in a coin it will ensure them a return visit to Rome.  The coin toss was seen in the movie Three Coins in the Fountain, with the coins tossed in by three different people.  Today, the current trend is to throw three coins into the fountain, using your right hand to throw the coins over your left shoulder.  I’m not sure if it works or not, but why break with tradition.