Well, Fish, the percentiles I arrived at were, admittedly, of my own guessing but I didn't come up with them just to back up my counter claims. There are solid reasons for my scepticism and pessimism that are, I happen to know this, shared by many others in the same boat.

You are right - I meet a lot of students and too few real linguistic over-achievers and good communicators. Why is that? I ask you: What have they acquired in so many years of formal classroom English instruction? Why do I have to accept blame for their failure to be effective communicators?

Look at the Chinese education as a whole, not just at the isolated English instruction. Mastering a language is something quite different from mastering a rocket science subject. It is more than knowing - it is a skill that needs training and honing and continous mental engagement. Do our students get encouraged in this endeavour? Yes - to some extent They get shepherded into their classrooms before classes actually begin, to do their "reading aloud" exercises. Do you think that a good way of instilling in them a sense of speaking English meaningfully?
In the evening they are again supervised when they do their "self-study", i.e. homework.

My wife is a Chinese English teacher and she has now after 2 years of teaching come to adopt at a very fatalistic attitude towards her charges: They are totally overworked and completely disinterested. In a class of 70, maybe 30 cooperate while the rest are patently obstructing interactive instruction.

The communicative approaches deserve mixed blessings even in western schools. They work under some conditions, but never with all students. In Chinese classrooms they look odd and students often maintain a negative view of them because they are utterly un-Chinese: "not serious stuff".
FTs are held in inferior positions and low esteem precisely because they have to do this "stuff" that's not "serious" by Chinese standards. 'Serious' is when the student has to memorise; practising is akin to playing and fooling around. At least that's the opinion of most Chinese parents and students.

Why don't Chinese teachders use English in their classes?

That is why students are manifestly unable to use English either as a medium of insruction or a language to converse in. It is a pure academic subject for them, irrelevant to most and unliked by the vast majority.

By the way, if your sutdents don't love reading English fiction they will hardly develop any curiosity about the language. Without a natural curiosity about it there can hardly be enthusiasm! Even teachers lack that.

If you don't address issues such as overcrowded classes, overworked students, unrealistic goals (do you know how the English of candidates wishing to go to university is tested and assessed?) then why do you think you can effect seachangesw on the psychological level, i.e. inspiring students and overcoming their culturally-induced sluggishness and inhibitions?