IIsn't NLP brainwashing?
What could be wrong with the assumption that actually there is no failure in second language acquisition? Why knowing a bit more about what is behind language learning can be brainwashing?
I'd just use a little bit of charm. Should work just as well as any other tactic
When I am in class as a student I don't want to be charmed by anyone. All I want, and actually am ready to pay for, is the result.
Needless to say, a good rapport helps a lot but only in case it has genuine disposition in the background