Awesome interview. A bit weird how closed-up he gets when it comes too the Nazi questions. By a guess, I'd say as most of German schoolkids who get the warstuff taught all the way at least four times in school, he just went into bored-mode, but didn't want to tell here and now.
Because really, by his words you would get the impression this stuff is covered up in schools - which it so massively isn't, that it probably has the opposite effect on pupils. For myself, I visited 3 different camp memorials during my school career.