Do you believe that an English major is smarter than a rocket scientist?
By the initial post, i believe the author is pointing out that someone who cant read or write can possibly play Bach better than Bach. That the content of what is written is more valuable than the structure of the grammar.
Too many, like you (apparently), Are so anal about the written style, that content is ignored. Perhaps its just your pet peeve. Either way, the content per individual still may have some importance. Even if you think the person is a complete fool.
Fools humble the wise. Because from the lips of fools comes a simple wisdom. And the wise get so arrogant about their wisdom, They can be more foolish than a fool. And perceived to have still said something wise.
No one knows all things. And every individual has experienced or been subject to a knowledge that only that person has gained. It is wise to treat all people with the same dignity and respect you desire for yourself. You never know, when the one you have belittled, may one day be a fireman that saves you and your families life. Or a nurse, who saves your baby when all other doctors and nurses had no clue what to do, and had claimed the baby would die.
I can not practise perfection. But i can practise improvement.
keep your mind from this way of enquiry, for never will you show that not-being is
~parmenides