That's true, but in the fifties, primary schools took care of this in our native language already. Clear and systematically. Which made the comparison with other following, (obligatory) languages more directly noticeable and gave assurance.
Unfortunately, I think, in this case, it is a case of post hoc ergo propter hoc. I think it is a lucky few of the kids who make the connection between their unconsciously learned grammar and the formal system some of us were taught in school. I myself (in the '60s and '70s) did not learn much "grammar" at school. When I took Latin in high school, I really started to understand (consciously) the grammar of English. How many kids in my Latin class? There was me. It had been canceled a decade or so before I got there, but I talked the teacher into teaching me one on one after he'd had a chance to smoke a quick cigarette in the teachers' lounge.
The truth of the matter is that a large percentage of the student body will never use grammar or algebra again after leaving school. The writers I work with are divided into two groups. The non-linguists who extol the teaching of grammar in schools as a panacea for everything wrong with today's youth and the smaller bunch of us who were exposed to some linguistics after having been scared with diagrams and parsing in Miss Thistlebottom's class.
