Your rush to judgment and the use of strong accusations when you are neither qualified, Nor Aware of the fact enough to talk.... as you do, it only shows that you are having some serious problems! of your own intellect!
Fair enough. For all you know, I may be stupid, but I don't believe I've left any questions unanswered, nor any of your attempts at a rebuttle unchallenged.
Basically, I feel you have made false claims that there are any benefits to invitro English lessons, if there even is such a thing. My reason for challenging such claims is simply that I don't want other readers to pop by here, read this, and believe such claims are indeed possible without actual evidence that there is said benefit.
So, if I haven't been clear about my questions, let me try again with a few new, clearly stated questions.
1. Where has this research to date been published? What journal? What have been the findings?
2. Who is funding the current research your friend has undertaken? What are the goals of the study? What are the controls?
3. If indeed your friend is conducting research and has had success over a three year period, why are you asking us for ideas on how to do this? Shouldn't you be referring to the professional journal that has published the results so far? or even your friend?
I'd appreciate some answers to the above questions before you insult my intelligence for the third time.