Honestly, I really haven't heard of him. But from your videos, his talent is undeniable. Thanks to you, I am moving to wikipedia and youtube to search for more details about him ;D
Btw, just saw that you're from Bavaria. I lived there for about half a year and I only manage to pick up some German. All I have to say that, German language is definitely challenging but it's a very interesting language :D
Don't feel bed, hardly anyone has heard of him, he is indeed an unsung hero. Yes I am from Germany, but German is my second language. The "der, die, das" is the thing that makes German most difficult for people to learn after childhood. Because the adjectives and cases must agree with the gender of the word, if you get the gender wrong, it causes a snowball effect of mistakes.
It's fairly easy to learn enough to communicate, but to use it without mistakes is extremely difficult for a foreigner IMHO.