Okay, but then I presume you're implying that you're a native speaker of a European language and my statement doesn't apply to you.

I expect people who are not native speakers of English or other European languages to be helped by the annotation. My girlfriend and many of my colleagues here in Asia speak natively only East Asian languages. Some of my colleagues are native speakers of both English and one or more East Asian languages, and I don't expect that they would find the grammatical notation to be helpful to them. I also don't expect my colleague who's a native speaker of French and Chinese to be helped by the annotation, even though his English is obviously a second language. But, that's just my intuition based on living and working in East Asia.