Felix Felicis não controla os outros, apenas faz a pessoa que bebe sorte.
“It’s liquid luck,” said Hermione excitedly. “It makes you lucky!”
Harry Potter and the Half-Blood Prince, Chapter 9, The Half-Blood Prince
Se o Felix Felicis fosse coercitivo como Imperius Curse, seria completamente banido.
“Now, I must give you warning that Felix Felicis is a banned substance in organized competitions . . . sporting events, for instance, examinations, or elections. So the winner is to use it on an ordinary day only . . . and watch how that ordinary day becomes extraordinary!”
Harry Potter and the Half-Blood Prince, Chapter 9, The Half-Blood Prince
Há uma ampla referência nos livros que apontam para o fato de que Felix Felicis orienta a pessoa a fazer escolhas que se mostrem corretas (sorte).
“Aragog,” said Harry and Hagrid together. Both Slughorn and Hagrid drank deeply. Harry, however, with the way ahead illuminated for him by Felix Felicis, knew that he must not drink, so he merely pretended to take a gulp and then set the mug back on the table before him.
The Felix Felicis gave Harry a little nudge at this point, and he noticed that the supply of drink that Slughorn had brought was running out fast. Harry had not yet managed to bring off the Refilling Charm without saying the incantation aloud, but the idea that he might not be able to do it tonight was laughable.
Hagrid twitched in his sleep and snored on. Slughorn and Harry stared at each other over the guttering candle. There was a long, long silence, but Felix Felicis told Harry not to break it, to wait. Then, very slowly, Slughorn put his hand in his pocket and pulled out his wand.
Harry Potter and the Half-Blood Prince, Chapter 22, After The Burial
Felix Felicis ajuda a pessoa que bebeu, manipulando os outros.