I have studied Shotokan karate ka for almost 10 years, and my grand master was called O'Sensai Tsurouka. However, I have a new Grand master in another martial art, who has third dan in Shotokan, and has never heard of Tsurouka.

Why is martial art so darn commercialised now...

Ok nevermind, I have found out who Tsurouka really is. We learn every day, new things.

HEHE... Tsuroka Sensei is the "father" of Canadian Karate. A great teacher.