I enjoyed your presentation about TEE but sometimes I hardly recognized some parts when the audience spoke. Anyway, I think you have a great sense of humor!(I'm not lying!)
Back to the fundamental topic, I think learning foreign language would be the most effective when teaching foreign language in it. That's because, as a person who learned English in almost Korean during secondary school, I have found it has some sorts of limitation such as knowing differences between synonyms. Also without TEE, both teachers and students can't prepare for the new type of English Test which will start in 2013.
However there are some practical problems to be solved. First, many old teachers in schools are not good at speaking English. That means, to start TEE, those teachers should be fired, isn't it? It will cause a CHAOS. Also, there are more than half of students in school who don't understand English-they can read words and sentences in English but they can't catch what teacher is saying. For example, when I was in the first grade in high school, my Enlgish techer asked, "Why are you late for this class? What did you do?" to a student. It's not a difficult question but she didn't answer at all.
(Maybe it was a little bit strange and topsy-turvy, I feel sorry about that.) Therefore, my conclusion is that TEE should be taken as soon as possible but TEEE should be sublated. To make a great Enlgish class and maximize the effectiveness in Enlgish class, TEE with mother toungue would be the best answer.