He has over 17 years too late to start professional courses in the art of Tae Kwon Do?
Do 17 is too late to start Tae Kwon? I learn because I feel great and want to self-defense.
17 is not old to start Tae Kwon Do. The only difference you should have with other Tae Kwon Do-ka began to practice from a younger age, they already know more than you. My teacher of Tae Kwon Do has started practicing Tae Kwon Do in the same age as you and now has a 5th dan, is a staff reviewer and teaches Tae Kwon Do a few hundred people. All the hard work and is very likely to get your black belt.