The criteria for a fully qualified ESL teacher are a degree in a language-related subject
area, preferably English plus appropriate teacher training that would be recognized for
working as a teacher at public schools in your home country, normally a PGC/DE from a
recognized university.

I disagree. If you omit 'ESL' from the above sentence, then you are correct.

I have never met an ESL teacher who has a degree in a language related subject, and for me personally, I feel that going to a Uni to study ESL would be pointless; if you are going to go to the trouble of learning how to become a teacher, then learn how to become a teacher, and not restrict yourself to teaching ESL.

Incidentally, C.I.T.A is a UK-based organisation that continually monitors the performance of its members. (Consortium of International TESOL Accreditation)

A person such as yourself, highly educated in the subject of 'languages' per se, is certainly qualified to lecture on the structure of a language. However, linguistics bores me to death. I much prefer the subject of 'Etymology' - especially since English is essentially a 'pot pourri' of Latin, Germanic, and a whole host of other languages.

Back to ESL and the following comment is not directed at you personally. It may seem a little flippant or trite, but I think you will understand the reason why I say it -

Academics on this forum may be fully capable of explaining the mechanics as to WHY we never say something such as 'I very like', but how important are those mechanics to an ESL student?

Sure, grammar is extremely important but the chances are such that if a teacher tried to explain to an ESL school student WHY we do, (or don't do) something in English, they wouldn't understand the explanation anyway.

Sometimes, just for the sake of sanity it's better to use the Chinese saying - 'No Why'

And as for us non-academics here, if we want to know something about linguistics we can just ask you - right?

Oh, the power of the internet !