How do you tell someone they don’t know that they don’t know? Is there some easy way to point that out?
If you don’t have any comprehension of local custom in a foreign country, say, and you make a hand gesture that is considered obscene, and others are outraged at your behavior, but you have no clue why they are upset…….does that mean you made an innocent mistake or were you remiss in not finding out such a thing before you arrived? If no one else was involved but you, well, I suppose you faced the consequences and learned your lesson, innocent or not. If, however, someone else was with you, say a youngster, and if the young person made the same gesture that you made, albeit, innocently, but the penalty for the accidently obscene behavior was going to jail — would it be the same? Not to me.
Singers who don’t know how rock music is supposed to sound (are there such souls?) and who sing it anyway they want (look for the person named “Wing” on YouTube, but brace yourself) have to take the consequences of their actions, which could include being mocked or criticized. Teachers of singing who don’t know what rock and roll sounds like (and it is NOT all the same, by any means), or what any style of music (sometimes including good classical singing) sounds like, but profess to “teach” it, are absolutely dangerous. They don’t know that they don’t know. And if you should be the unfortunate recipient of instruction from some such idiot, woe be to you, unless YOU know. But if you did know, why would you be a student in the first place?
If you think that rock is the same as jazz or that jazz is the same as music theater (and each of these styles has very wide-ranging parameters) simply because all music that isn’t classical is “that other stuff”, why would you assume you could teach it at all, let alone well? Because you probably don’t know, because it didn’t occur to you, that the music was worthwhile in the first place.