talks as though he knows/knew a lot

It's certainly true that some, the ignorantia, are still teaching ESL/EFL promulgating these old canards because that's the system that a lot of countries have used for such a long time.

Thankfully, it's not true for a lot of teachers. It certainly wasn't true for me. It didn't take reading linguistics texts to convince me. After about one year teaching ESL I noticed that students who followed these nonsensical prescriptions created strange English. The following years were spent uncovering the canards and exposing the charlatans who perpetuate this nonsense.

You must be familiar with the Pet Peeves thread.

Since you have such experience, why don't you just answer tanguatlay's question?

Done E, in Post: # 4,453,225 .

It's as important or more so, to staunch the flow of inaccurate information about language. There is oodles and oodles of that out there.

Ms Tan got her question answered and she may well have gotten a whole lot more. One important thing is that English does not have any set of rules that are variously described as Sequence of Tenses/Tense Agreement.

You all have, give or take some years, the same experience as I do. The difference is I got into a field where I was faced with these nonsense rules that have been much of yours and pretty much everyone else's experience for the last, roughly 250 years.