CalifJim

“
Probably not.  There may be a better way to finesse this with a different wording.

Yes, but from the viewpoint of the authors and the teacher, this may be considered a harmless "white lie".

Out of curiosity, does the book actually use the words, "serious grammatical error"?  Or is that your impressionistic paraphrase?

”

Thanks CJ

"Serious grammatical error" is my paraphrase.  But when and if ESL students start to expressly state "this IS an exceptional usage", I suppose that means "these is a set rule on this and no one can break that in any shape or form".

"the simplification of the grammar at the beginning makes it much easier for them to navigate the language with confidence in the beginning stages" ...  I fully concur with your view here.  This indeed is the ideal way of teaching something to someone, I would say.  However, the reality is that they will soon start feeding what a SVOC is, along with modifier/qualifier, the difference between a relative pronoun and adverb and all that good stuff to students who even cannot pronounce the word "English" correctly yet.  I have an impression that they do present "grammatically acceptable" sentence structures, rock-solid rules and what not all at once.  It is not a fun way to learn a foreign language.  That is why some students grow not to like the subject after short while. 

Let's say you are in a store with a hardcore grammatical ESL student, and you say:
*&@!#% !!  I just realized I left my wallet home!!
... in stead of saying "It's all right, CJ, here, take $100.  You can pay me back tomorrow.", (granting that he/she understood what you said), the ESL student will be too busy thinking "Why did he not say "I HAD left my wallet"?  Because he is describing an event that happened obviously prior to the moment "he realized", it should be the past perfect tense, thus "I HAD left".  It could be an exceptional use of the "realize ... that ...." structure but I am not sure.  Or should I just point out his grammatical mistake?" ... this is the mentality of students who are being taught by those hardcore grammar books, and I am not exaggertating even a bit.

Thanks.