TPRS works.  This is an essay that a Spanish I student (non-native and no background in Spanish) did in class. Before teaching with TPRS my students never came anywhere close to results like this.  

Student read Blaine Ray’s Patricia va a California in Spanish 1 over a period of 11 days.  Many techniques were used.  They read individuality and with partners, talked about it, acted out parts of it, and got background information about Guatemala.   All work was done in class.  No homework.

The challenge assignment for students that are advancing more rapidly was to re-read and then close the book and summarize each chapter.  This is a bit too long of an assignment, and I do not normally assign work like this–I do not think it would work for every student–but the advanced students actually relished it. They were to summarize, not re-write, each chapter and they could not copy any sentences from the original. They could not use a dictionary. I normally do not correct much on student work like this, but this student wanted it, so I underlined the (remarkably minor) errors for her.

Click on the link to see the entire essay: http://www.brycehedstrom.com/wp-content/uploads/2011/09/Patricia-va-a-CA-Student-Summary.pdf

It is the method, not so much the teacher.  My student teacher did most of the instruction for the unit on this novel.  I coached her and gave her ideas and materials, but she did the teaching.