As I mentioned on February 19[-ish], in my class, the textual analysis was done and over with before I even thought about this assignment, so as such, I did not use my personal sample with my students. I did, however, give them step-by-step guidelines in how to develop and texual analyzing argument, which did prove equally beneficial without the drawback of pressuring my students to "imitate" me (thanks, Eric, for articulating that thought for me!). I first had them summarize their article, then outline the article in such a way as to have each point be the article's evidence (this helped them identify their criteria), and finally, write a practice analysis in groups of 4-5. The latter bit was done in class, that way, if they found that they didn't understand a particular aspect of the assignment, they could ask me in person when the problem arose. It was very effective.
I did, however, use samples for the memoir assignment. In fact, in my class, this assignment is the final, culminating assignment of the semester where they get to "strut their stuff" and show off their skills. As such, I began bringing in sample memoirs from high school all the way up to last semester, covering a number of genres, for workshop and freewriting days. I was clear in that this was no attempt to show off my writing or to push them in any one direction, but rather to help them brainstorm and get an idea of the wide range of options just within the memoir genre of writing.
We're still working on this assignment, obviously, so I don't know yet how this will shape up, but I've seen faces where, suddenly, a lightbulb goes on and they realize that this might be bigger and better than they expected, and, Holy Ballpoint Banana, Batman, this writing assignment might even be *gasp*
fun!