To this day, I'm not sure if the player character is meant to be genuinely unable to communicate with anyone save through rhyme or just taking the piss at everyone around him. Given the player character DOES communicate clearly several times in the game, there's actual in-game evidence he's just screwing with people. Given he acts like no one with real mental illness does while Malkavians like Jeanette and Theresa are much more traditionally Malkavian, it makes sense that the PC is just pretending to be a off-beat poet of lunacy.