Obviously there is a fairly significant amount of effort that goes into language instruction on the part of the teacher and students, but I feel that if such variables could be empirically be measured, language teaching has probably the most abysmally low outcome per effort ratio of all disciplines. To be linguistically competent, hundreds of consistent man-hours of study are typically required, and after such, one's domination of a language is not necessarily useful or admirable. This has been the longstanding dilemma of instruction for young adults and older.
Of course of all the developments in language teaching that occurred in the
past century, probably the most interesting took place outside of SLA academia
and in the company of a subtly charismatic polyglot and holocaust survivor
later based in Beverly Hills. Michel Thomas was a bizarre figure who spent his
days offering his teachings services to various celebrities and the wealthy;
they would be taught for the equivalent time of a weekend or so and would
afterwards garner a considerable functional grasp of the language of their
choice (French, Spanish, Italian or German). But for all the
well-called-for doubts, Thomas did manage to produce a number of celebrities with a useable fluency in their target languages.
The Michel Thomas Method, as it is oft called, continues to maintain a foggy and mysterious aura which was very much cultivated by Thomas himself. He would lament of the pains and stresses of book-learning and say that his method avoided such undesirable feelings by placing the obligations of teaching on the teacher. In the audio tapes of his lessons which would later be marketed, he would remind his learners "never to try" especially to remember vocabulary and forms because, “what you know you cannot forget.”
Now it should be obvious to say though, that learning doesn't simply fall into place from feel-good verbiage and wishful thinking. If anything, idly saying that Thomas could facilitate learning just by putting his patients at ease profoundly ignores what should be the real source of the efficiency of his method. It is indeed a quite unique one and one worth studying and imitating. Of course the course did make the students try to think, and perhaps even more drastically, enjoy thinking.
In
the audio tapes sold on his website for public consumption, Thomas is
recorded for 8 hours teaching two native English speakers whatever
chosen language. He approaches gradually new concepts while constantly
asking the two participants to produce new recombinations of known
words; he corrects any errors.
Having listened to a number of Thomas's tapes, I think there is a fairly systematic linguistic order of operations maintained along with a general teaching style that is so divergent from other language learning equipment in key points. There are two reasons that I think account for the success of the Michel Thomas Method: firstly the presence of non-native learners who make mistakes that are corrected, and secondly the format of the course which caters to verb-based generative grammar.
Most language materials, especially other types of audio tapes simply limit their explanation of grammar to what is correct without necessarily predicting and correcting grammatical miscalculations on the part of the learner. There seems to be a general fear of letting the listener hear any phrase that is in fact non-grammatical in most of these programs. Thomas, however, is a master of error analysis and his method uses the unplanned errors of the other learners on the tapes to clarify possible misunderstands and to simply rehearse what is difficult for English speakers to internalize. In a sense, the audio-listener has to at least have as deep as an understanding as the two participants and many of his grammatical assumptions are called into question by the correction of the errors of the participants.
To the second point, Thomas does not begin his lessons with vocabulary lists or by telling the listeners to remember the days of the week; instruction is strictly practical and strictly generative. Learners are first typically taught to recycle Latin cognates with basic expressions of existence and purpose. The first sentences are of the nature of "This is comfortable for me." and "That is not acceptable like that." Thomas builds on the basic framework of expression modal verbs such as want, can, should, must etc. combined with simple pronouns "I want to see it." and "He cannot know this." In an hour or so, the learners are not just repeating mindless requests to mind the subway like some horrible Pimsleur tape gone wrong, they're gaining the capacity to generate their own sentences with new verbs and with an intimate knowledge of each one. They are never asked to repeat, only to produce new sentences based on formerly learnt phrases and verbs.
One of the great economical aspects of the Michel Thomas method is that it supplies the learner with a colorful array of expressive verbs, but only introduces nouns when strictly necessary. In any language, but especially in European ones, verbs are the most fundamental part of language as they communicate the most important relation of the sentence. They are also mandatory; there are pronouns, but no pro-verbs. The fact, as I believe Thomas recognized, is that the framework of a language, including one's fluency in it is based on verb use. Nouns can be filled in later or talked around quite easily; he in fact admonishes his listeners that it is appropriate to guess on nouns, but never to guess on verbs as that nearly necessitates being misunderstood.
So his method is just as well marked for what it doesn't cover as for what it does. Listeners are never burdened with memorizing words because the words introduced are useful and constantly rehearsed in the content of the tapes. Thomas only integrates linguistic elements that are necessary for stimulating a generative grammar and a voracious desire to continue learning after the end of the lessons. So what sets this apart from other language learning instruments and especially audio is the fact that it dives directly into the most essential aspect of being fluent in a language, the capacity to produce new phrases and helps the learner perfect it with the right amount of correction and at the ideal speed.