Though it's not something I do (without cause), "taunting" your opponent is a legitimate strategy as it can cause them to become flustered which can lead them to making mistakes. It's a mind game that's been played for ages. It's morality is questionable. I personally find it bad sport, but I can't deny it's legitimacy. The best thing you can do is not let it affect you. If you get the chance, you can even try to taunt back. If you don't let it affect you, there is a chance it will affect the original taunter and cause them to make mistakes as many of them are just immature youth who can't control their emotions, putting you at the advantage.