The joke went over Rapunzel's head completely. She didn't even stop to think about it because she was too set on getting on to the actual boat. When he released her she tugged her braid along to board the boat with the fearless resolve of someone who was more akin to sailing than she actually was.
"Because of your magic, right?" she had been paying attention to him before when he spoke of his illusions and she was just as eager to see those as she was the boat.
Rapunzel scampered over to one side of the yacht and curled her fingers around the railing as she peered into the water. Then she glanced over her shoulder, smile uncurling playfully.