I’m impressed by the sheer number of Arabic-related pet hates I’ve apparently collected in such a short time! Well, none really concerning the language itself, but mostly with respect to the speakers instead. To be honest, this is the best piece of advice I’ve read I can kind of already relate to:
Modern Arabic-speakers learn Standard Arabic at schools and from the media. Many of them have only limited understanding of the grammar, because it is significantly different from the grammars of the modern spoken varieties. For this reason it is never a good idea to blindly trust what a ‘native’ Arabic-speaker says about Standard Arabic grammar. Standard Arabic is not a native language to anybody. The only good reference for Standard Arabic grammar are the books.