I believe that ESL supporters of "Target Language classroom immersion" are being given short-shift here.

Although I am not an advocate of this teaching philosophy, especially in an EFL context, I do respect their views. My TESOL professors at Columbia in New York, all PhDs in linguistics, benchmark textbook authors, were adamant about eliminating the native language from the classroom for ADULT learners.

This was in the mid 1980s and I am not current on second language learning research, but I'm sure that there are many qualified language teachers that continue to support the methodology of a "pure target language" classroom for adult students.

In reality there are no 'child' second language learners. Prior to puberty, children acquire language in a manner distinct from adult learners. Pinker and Chomsky may argue about the nature of the physiology of this process, but not it's existence.

An issue to consider in China is the unique status of the 'waijiao' in a Chinese University or High School. Students receive training in English grammar, reading, writing, pronunciation, vocabulary, etc., from Chinese teachers. The history and legal directives on this are interesting (I'll leave them to Turnoi to discuss if he likes). But the fact is that the FT in China is relegated to a diminished teaching role. His students are receiving varying degrees of Chinese language support in their classes with Chinese English teachers. It could be argued (and often is by foreign language department deans in China) that the role of the FT in China is precisely, and merely, that of a 'usage model', what Community Language Learning (CLL) labeled a 'robot', for students to access during their personal 'struggle' with listening comprehension and oral English (generally considered of secondary importance in Chinese education) in the English only classroom. In every Chinese University, Chinese professors jealously guard their 'integrated English' courses against FT intrusion.

I believe that all language 'teaching', certainly all language learning, is 'integrated'. I routinely use Chinese in my class and find it valuable for many purposes. But I respect the views of teachers that have beliefs that differ from my own.